@Bali1 there is a lot of evidence that sealing the chambers of piston regulators can be far worse for them than leaving them unsealed because anything that gets in, won't come out. 2 years of salt water sitting on that piston will cause some serious damage. 7 ports is excessive, the swivels are better because they will adjust with need. Typically that is turning your head or donating your regulator.
@Dnaber I would argue that of the three, the Atomic is going to be the best quality and performance of the bunch, and has the added benefits of being made in the USA. allows user servicing, and doesn't have a warranty contingent on a yearly service interval. For that, I will never new purchase Aqualung regulators *including Apeks*.
@cerich Hollis claims that all of their metal parts and assembly are done in the USA, I'm not entirely sure I believe that, but I have it in writing from them, but of the "big name" regs that are made in the US, Atomic is the only one I would personally go with. Argonaut Kraken is also made in USA, but is a double hose and isn't a "big name"
Quality is very subjective since most of these are done with injection molded and CNC machined parts, so the Asians can make regulators just as good as we can and just as good as the Brits and Europeans can. It is all in the design, and I think of the lot that you listed, the Atomic is going to be the best.
I would also consider looking at the Argonaut Kraken, it's unique and different, but in a good way, especially if recreationally diving. I've used a couple of the prototypes and they're snazzy. If almost all of my diving wasn't cave diving, I would already have one and may well treat myself to the new one this year just for fun, but it's $600 not $400. Unfortunately you just missed the big xmas sale from Deep6, but for my money, restricted to buying new today at ~$400 msrp, I'd get either the Deep6, or the Dive Rite XT. Both similar designs, Deep6 I think is better, but it's splitting hairs. Both are nominal $400 for just a first and second, or nominal $600 for a full single tank setup. I would recommend getting a full single tank setup personally so everything is standardized, but to each his own.
