IMHO GUE Rec3 is just not very versatile. Yes it allows you to dip below 100ft for short times. But 21/35 really is overkill for a 120ft dive. 25/25 is totally adequate for that and saves you quite a bit of money at current helium prices. Additionally the 32% "ascent gas" is a terrible choice for actual deco. I'm sure it works fine after the 10-20mins you might spend at 120ft. Particularly if you then do a long slow ascent swimming upslope. For a free ascent to a boat, 32% is not really "accelerated deco". The only other people using this combination of gases are other Rec3 people - and possibly your local instructors since the 32% ascent gas is not a standard gas in this application.
When you start talking about 60min 100ft average depth dives, GUE Rec3 does not give you access to oxygen deco gas you need for this kind of profile.
UTD Tech1 gives you access to 25/25 and O2 with up to 15mins of deco.
GUE Tech1 gives you access to 21/35, 30/30 and O2 with up to 30mins of deco.
Either one addresses planning and gases for 60min at 100ft type dives. GUE Rec3 does not and UTD Rec3 is a no-deco class.
As a GUE Rec3 graduate
(first in the USA!) and current UTD T1 diver
(finishing UTD T2 soon), I would have to agree that Rec3 is not very versatile in terms of where you can explore at the deep end of the range. 32% as a
deco gas from 70' is, honestly, a bit silly. If you want to do 60 minute square profile dives at 100', I agree with most everybody else that either GUE or UTD T1 are probably better options. UTD T1 is a nearly perfect match for a lot of the diving you're asking about. GUE T1 will be more intense and take you deeper/longer
(UTD T2 is the equivalent level), and will let you do those dives off the BAUE boats and at BAUE events
(don't ignore that benefit). All that said, Rec3
does actually work well for a fair amount of "mid-range" diving we have at Point Lobos, and for some of the pinnacles we have for boat dives, once you understand the dives folks like Beto actually have in mind for R3 divers.
The key to understanding effective Rec3 profiles
(as Ted/Ben alluded to - they've done the dives with me 
) is that you're looking for sites that allow you to effectively enjoy a second dive while you're doing your minimal deco. Deep shore diving with a gradual (and beautiful) return trip like Point Lobos is great. Pinnacles with interesting scenery and life distributed from 120' to 30' are great. Here's a typical R3 dive for me at Lobos...
- Scooter out to somewhere like Betos (good length surface scoot, then staying ~100'), enjoy the scenery during the trip
- Descend to ~120', have a nice ~15 minute tour around the bottom
- Ascend to 90', scoot above the site and start heading back in
- Gas switch at 70' (Sea Mount)
- No faster than 10'/min (easy to maintain) to 50' while swimming or scooting back in (maybe pass by/enjoy Hole In The Wall)
- Head over to Middle Reef, stay above 50', and enjoy a nice dive going deep -> shallow for basically as long as you care to and have 32% for
- Do your 20' stop and 5 minute ascent, get out, eat lunch :eat:
That's on scooters, and it's a nice, fun dive - especially when vis is good. Total runtime is usually between 50-80 minutes. You do a similar thing on pinnacles, but without so much travelling. Square profile R3 dives where you drop to the bottom, do your time, do your planned deco, and get out of the water are stupid and boring IMO. When you get some experience beyond class, run a few hundred experimental profiles in deco planner, start thinking about the actual average depth on dives like the one I described above, use your brain, and realize that you're actually able to do a fair amount of neat diving at Lobos with this cert and a scooter
(or a long surface swim).
You also get access to 30/30 with R3. The only problem is that since it's a 100' gas nowadays 30/30 is stupid, expensive, can't be quickly blended as 32% + He, and doesn't actually save you substantial amounts of deco time in this range. 25/25 is a better choice IMO, and covers the entire R3 range, but if you're diving with GUE/BAUE divers you need to make sure your team is on the same page with you - it's not a GUE standard gas.
FWIW, the only reason I'm not taking GUE T1 is because UTD was able to put together a competitive class package for me
(that GUE teaching standards disallow) that involved doing my training the way I actually do 99% of my dives - on scooters at Lobos. I'm not a big boat guy
(as Ted and Ben can also attest to ). Beto is a fantastic instructor, I loved class with him, and I highly recommend him to everybody.
how to use them would be a very good thing.
