rEvo vs JJ CCR (or others) in a cave

[dmainou]

Hi guys,

Met a cave diver that dives a rEvo and was bragging about how much better the rEvo is inside a cave than a JJ.

I'd like your opinion about the veracity of his claims as I'm conscious of his animosity towards the local JJ dealer and acquaintance with the local rEvo shop


I haven't come across that many rEvos and I'm not a cave diver.

Amongst many other things he said that he could take the rEvo into tighter spots. Does the shape of the cans makes a big difference on a regular basis?

I've heard that the rEvo has little flood recovery so....

Anyway, since I'm not a cave diver, I'm happy to listen to more educated people than me.

D

[Johan Isaksson]

I'm both a cave/mine diver and a bit of a wreck ferret. I was debating rEvo vs JJ when I got a rebreather and was set on a rEvo for years before I started training.

I ended up with the JJ for many reasons but one of them was that it seemed, to me, more suitable for the dives where I'd personally would have the biggest benefit of a rebreather. This is mine diving with admittedly less restrictions than proper cave diving but plenty of swimming distance in an overhead environment. To me the benefit of being able to do flood recovery to stay on the loop outweighs the lower profile of the rEvo. If it gets tight enough for that to make a difference it's likely sidemount time anyway.

I might buy a rEvo too since I love the design but I have no regrets with my choice.

[DSix36]

I dive a rEvo and am a cave diver too. I am one of those people that will wiggle like hell to get through a tight spot and my rEvo II is the absolute lowest profile of any other rebreather. It is true that it has very limited ability to drain water from the loop but that is something I am prepared to deal with; I do carry bailout gasses.

So far I am very happy with my rEvo and have not seen any other unit that will suit my style of diving better. Mr. rEvo (Paul) is constantly working to improve his design and technology.

[jcook]

I would go with a JJ, way better WOB, easier to breakdown for travel, use of any size tanks, etc. A lot of time and effort was put into the JJ to make it a great unit by rebreather divers who know what they are doing. My only thing that would keep me from buying the JJ is the scrubbers. I am not a fan of their little scrims on the radial scrubbers. Plus the JJ is truly CE, not just skirting around the CE standard.

I would stay away from the rEvo like the plague. I also almost bought one as my first rebreather, I actually was about to send the money to pre-order a rEvo III before they came out. Then I got to see one in person, that was it for me. It isn't made anywhere near as well made as the JJ, the cell placement sucks, build quality is crap, no flood recoverability, etc.

It is like buying a Jaguar or a BMW, one is beautifully made and sexy, the other is an engineer's wet dream that works.

FWIW I don't own either unit. I dive a Meg and have owned a few other units. I have about a dozen hours on a rEvo and zero on a JJ. I know they guy on the forum that has the precursor to the JJ though and it is a beautiful unit. You will hear people say the rEvo is the thinnest unit out there, but as a fact, it isn't.

[Dave Sutton]

Have on hand here one of each of the following:

JJ, bone stock with BOV

rEvo, Standard SS Hybrid, Shearwater powered (non-RMS)

Meg, APEKS with Shearwater inline.


I respectfully disagree with the above post, the rEvo has excellent build quality, is flexible, and is very robust. This is based on over 5 years of faithful service to me in dives ranging from caves to surf to deep wrecks including multiple trips to the Andrea Doria, etc.

Where the Meg and JJ beat the rEvo is in water tolerance: What water the JJ and Meg laugh-off causes the rEvo to need to be bailed-out from. If you can accept that, then the rEvo is a very good unit, superb in fact.

The Meg (although you didn't ask) is the military-level top of the line at present and being that it is USN and NOAA issue as well as being CE places it into a category of it's own.

The JJ seems an excellent unit. It's more compact than the Meg and has nearly the same water tolerance. I really like it, and think it'll soon become one of my favorites.


You need to dive each of them to see what you like best. I've dived the rEvo most of all of these rigs, the Meg second, and am now just playing with the JJ. I would be very happy with any of the three if I had to choose just one "for the rest of my life".





Dave


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[dmainou]

Quote: (Originally Posted by Dave Sutton)

The Meg (although you didn't ask)

Thus why I added the "(or others)" bit.

I own a JJ and love it. However, I realise that I have only owned a JJ. I have low number of hours on it and no experience on other units. Therefore being conscious of this thought in asking on this forum.

I equated the comment of being "able to fit in smaller places inside a cave" to saying that my car is better than yours because it has flames painted on the side and because it steers better on tight curves whilst going in reverse...

That is, whilst disregarding all other scenarios the rEvo outperforms the JJ (and all others) on a very specific dive, never mind the other pitfalls that the rig has such as flood tolerance, etc.

I know that they are all tools for the job and as long as you pick the right one you'll be fine. Money is a limiting factor but....

Anyway, thanks for confirming what I thought.

Dave,

One last q.

Side by side, how thicker is the JJ including plate, lungs, etc?


D

[PeterN]

Any one who makes extravgant claims as to the superiority of any of the above units is quite silly IMHO.

This summer I was exploring a cave up here with a Kiss diver, one on a rEvo, and me on my Meg. I do believe I got a little further into some tight spots than the others, this is probably more a function of my poor judgement than anything else.

All units worked fine all week.

I think I could get into tighter spots with rEvo than the others and look forward to trying one out sometime.

The rEvo is beautifully built and probably the most technologicaly advanced unit generaly available.

For me I like that my Meg comes apart so easyily for reasembly in remote places. When I purchased it, flood recovery seemed important.

I had a JJ here last winter. Lovely bit of kit and a worthy contender.

To me the Kiss seems a bit dated, but I go out with with them fairly often and they seem dead reliable.

Where you want your counterlungs seems one of the first issues to grapple with. Once that is settled, find a unit that is supported localy and suitable for the dives you plan to do. After a couple of years you will have very different ideas about what matters and you can switch if it then seems important.

Good luck,

Peter

[Packhorse]

I dont cave dive so take what will from my post.

I think the rEvo is very well designed and built. I really cant see where jcook is coming from.
For the dives I do I cant imagine a better unit.

Cave diving could be a little different though. When things are going good the rEvo may well be the better unit. More efficient sorb use, lower profile, good WOB.

But from what I understand flood tolerance is lower on the rEvo. Having said that I have never had a flood on mine. It could also be argue the the rEvo is less likely to flood than other units.

So, do you go for a unit that will perform better on all the good dives or a unit the performs better when something goes wrong ( where you should probably bail out anyway)?


Given the choice of the 3 units.... you probably cant lose. You just get different pros and cons.

[Dave Sutton]

Quote: (Originally Posted by dmainou)

Dave,

One last q.

Side by side, how thicker is the JJ including plate, lungs, etc?


D

Uh... an inch? Two? It's really not a lot, but then again: I remember in the Viet Nam war that guys complained that the new jungle fatigue buttons were too thick compared to the old flat buttons on the old green fatigues... making it harder to lay FLAT when being shot at. When fractions of an inch count to guys the rEvo has the edge. To me, it's irrelevent.

With that said I am packing both the rEvo and the JJ later today onto the boat and I can probably wrangle up a side by side photo of their thickness.

As for me, I cave dive but I am not a "squeezer"... I don't like to scratch the crap outta my rigs, so... an extra inch makes no difference. The small difference in flatness is not made up by the lack of water tolerance of the rEvo, and mechanical "toughness" counts too, so the Meg (which is the "thickest" of all) is my cave choice. This is my personal opinion, others obviously vary.


I'd challenge the above post regarding WOB between the rEvo and the JJ and ask for numbers to back up the assertion. I'd also challenge the "skirting the CE" statement and ask for facts as well. Statements written as facts ought to be based on facts, and with the stakes here being that purchasers may make choices based on what's put up here in the forum, it's only fair to back up "facts: with, well... facts. I take neither of those statements seriously at present, particularly when coupled with opinions on build quality that are not able to be resolved against the opinions of many others, including users and owners.

It's kind of fun to sit in my seat as the owner of essentially "one of each" without any emotional investment in any particular unit. I can see advantages and disadvantages in every rig built, and have never found the perfect one. Right now it's JJ/rEvo/Meg all tied for "best".

Rankings:

Compactness:

rEvo
JJ
Meg


Electronics Sophistication/redundancy:

rEVo (ahead by a long shot with the RMS system)
Meg (Apeks with Shearwater secondary and HUD)
JJ (all Shearwater, still damned good)


Water Tolerance:

Meg
JJ
rEvo (behind by a long shot)


Mechanical Toughness:

Meg
JJ
rEvo


Cylinder Flexibility:

JJ
Meg (can hold anything, just not as easially as the JJ)
rEvo (far behind either)


Backplate Flexibility:

JJ.Meg tied (both re-use your existing OC backplate)
rEvo (uses it's own backplate, not compatible with OC plates)



What else?




Dave

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[jcook]

Quote: (Originally Posted by Dave Sutton)

Uh... an inch? Two? It's really not a lot, but then again: I remember in the Viet Nam war that guys complained that the new jungle fatigue buttons were too thick compared to the old flat buttons on the old green fatigues... making it harder to lay FLAT when being shot at. When fractions of an inch count to guys the rEvo has the edge. To me, it's irrelevent.

I'd challenge the above post regarding WOB between the rEvo and the JJ and ask for numbers to back up the assertion. I'd also challenge the "skirting the CE" statement and ask for facts as well. Statements written as facts ought to be based on facts, and with the stakes here being that purchasers may make choices based on what's put up here in the forum, it's only fair to back up "facts: with, well... facts. I take neither of those statements seriously at present, particularly when coupled with opinions on build quality that are not able to be resolved against the opinions of many others, including users and owners.

Hmm, didn't know you served in combat Dave.

Ah, well that's all and good if you don't want to believe me about the WOB for either unit, but you can look at the test of WOB in joules that are published for either unit. I believe the JJ has better WOB than even my old Boris, 1.57 J or something close. Too bad rEvo's aren't 3rd party tested for anything...... Plus in proper cave trim, the rEvo sucks. I have experienced it and I hear my friends complain about it on their rEvo's. They swim like wreck divers in the cave and I have to come up and adjust them underwater.

As for the CE problems, just take a look on RBW at Paul (guy who makes the rEvo) trying to cover his ass with basic questions from people about his CE testing and the standards he is using.