My plastic & webbing thingie is also a pre-owned Aqua Explorer band - I'm really glad I didn't buy a brand new one, or that the wife didn't buy me a new one for my birthday before I bought the used one.
I'm kinda on double-secret probabtion for dive gear accumulation currently - like someone else posted recently. We're being transferred, and she made me put all the dive stuff I got a good deal on, that then didn't work out for whatever I was trying to do, in one big box as she was cleaning the bedroom which was an office but became 'the scuba gear room' while we lived in this house. Once we get resettled at a new address, I'll be putting it up for sale - all of it that went in that one big box. That's where my AE kit is. Someone else can make good use of this stuff maybe.
I don't dive cold water, so freeze-up freeflows haven't been a concern for me. I often dive independant doubles on plain old recreational dive profiles, and stay within no-deco limits, when we're doing photography and such. My petite wife / dive buddy has about half the RMV I do, so it works well, and we don't do this when diving from boats with groups who need to stick to a schedule. More for when we're shore or boat diving either by ourselves or with just the DM. it gives a nice mix of time at deeper depth as well as extended time at shallower depths on a multi-level profile. One of the best applications I experienced for this approach was when we dove Angel City and the Hilma Hooker as one dive together on Bonaire - enter at Angel City, do the outer reef, then go to the Hilma Hooker, exit at the Hooker, unharness on shore, and I wait by the gear while the wife walks back to the truck, and drives over to load up and go back for a snack and a SI. This works really well if she dives one 63 ft3 and I dive with two 63 ft3 tanks. She's petite and prefers 63's. Or, if she dives one 63ft3 and I dive two 50ft3, if that's available. it just depends. Or, sometimes I do this with two 80 ft3 and exit with more gas remaining. And yes, for no-deco-obligation dives, at least 500 psi in each of our 3 tanks at the end of the dive.
I also did one of my tech cert checkout dives using independant doubles, the others were all with pre-manifolded doubles. Worked well both ways.
I do keep the reg switches to 2 - just like wedivebc wrote. If doing deco-obligation dives, absolutely, turn after using 1/3 of the gas from each tank, but that doesn't necessitate a reg switch when you turn back - just keep breathing from the second tank until 2/3 of the gas is gone from it. Then, I do the second switch after 2/3 gone from the second tank, back to the tank only 1/3 was used from - the tank I began the dive with.
