I decided to get the Atomic B2. The other regs under consideration were the Scubapro MK25/S600, Scubapro MK17/S600 or S555, Oceanic Delta 4, and the Atomic T2.
I eliminated the T2 because of its steep price and the Titanium/Nitrox issue. The Atomic manual states that if compressed air is used with the T2, it must be cleaned prior to using Nitrox. These two issues eliminated the T2 for me. I want a reg that I can use with compressed air or Nitrox and be able to switch between air types.
To help me decide which of the remaining regs I should get, I looked at where they are serviced in the Puget Sound area and in Florida, near my Florida home. I'll move back there in a few years and I'll want to get service for my reg when I go back. The dive shops closest to me in Puget Sound and Florida both sell and service Atomic regs. In Florida, the Oceanic sales and service is 40 miles from my Florida home. The Subapro sales and service is 20 miles. The Atomic sales and service is 10 miles. All of the shops are good and reputable. Advantage Atomic.
Then, I asked myself which of the regs I would prefer to have based on performance only. Again, Atomic was on top. The others were close, except for the MK17/S555. At this point I eliminated the MK17/S555 because I preferred the adjustable second stage.
Finally, my LDS here in Puget Sound was selling the B2 for $579. The MK25/S600 was $598. The MK17/S600 was almost as much. The Atomic B2 DIN wasn't in stock, but they said they would order it for the same price ($579). Sold.
Thanks everyone for your responses. Let's dive!
Ron