Please do not tell me that I need to buy a BP/W. If I ever decide to tech dive, I'll buy one then.
I plan on buying either the Black Diamond of Balance from the LDS within a week or two. I would like opinions/comparisons of them. The both have their pros and cons. Here's my take one them. Please add your own. I'm especially interested in hearing from anyone that has been diving in both.
Keep in mind that 90% of my diving will be in quarries with a thick wetsuit with an occasional (once a year) vacation with air travel.
Black Diamond
pros
Lots of pockets and D rings
a lot of lift - 50#
convertible to handle doubles
can handle a lot of lead (32# ditchable, 10# trim)
cons
heavy and bulky to travel with
less streamlined in the water
Balance
pros
Light and easy to travel with.
more streamlined
cons
less lift 36# (plenty for a single cylinder)
with a 7mm farmer john, I'll have it close to maxed out on lead (20# ditchable 10# trim)
less pocket space
FWIW I'll also trying to decide on getting the air2 option on either and an open to opinions on this too. I have a perfectly good octo but it would be nice to have one less hose. Hopefully it'll never be used but I have no problem donating my primary in an OOA situation.
I'll edit this post and add any pros and cons that seem relevant to me.
I don't see lots of pockets, drings, and 50lbs of lift for a single tank bc to be advantages. Rather they loan themselves to being all boogered up with unnecessary junk. It may say it can be converted to doubles but that is a load of crap. It will be a jury rigged setup(factory but jury rigged nonetheless) and 42 lbs of lead in a bc is just dumb as well as completely unnecessary.
I personally would not buddy up with somebody who expected me to help them put a rig with that much weight in it on. Hell that's damn near what a set of doubles weighs when you add the tank. And putting all your lead in a bc when diving cold water or with heavy exposure suits is also less than a genuis move. Distribute the weight between the bc and a belt or weight harness.
If you already have an octo why go with an AIR2? One less hose? How long of a primary are you going to switch to? Hopefully a minimum of 40 inches or better yet a 5 footer routed under the arm and around the neck. How many times have you done an air share ascent with an AIR2 or similar? More importantly how many times has your buddy? Just don't see the logic here.