SouthFlorida, My wife and I both (previously) had Atomics - and they were both noisy. We sent them back to Atomic numerous times and Atomic even replaced one of them. Yet, the noise continued - even in the new replacement. We sold both of them and now have Oceanic EOS's. In my opinion, they breathe even easier than the Atomic, they are far more reliable, and they are quiet.
Atomic dive equipment is like Apple computers..... After people pay double what they should for them, they are afraid to admit (or in denial) that after paying so much for something, they could have gotten something as good or better for much less.
Go with the Oceanic EOS!