Atmos for headphones requires a one time, $15 license purchase, and works with any headphones. So, all headphones, including all gaming headsets that cover both ears, will work with Atmos. Atmos has, by far, the most content that is optimized for the system. So, that's what I'd be going with.
As for a headset, I'd just audition a few and return all but your favorite. Sound perception is a very personal thing, as is headset comfort. So, auditioning is the accepted best-practice when choosing audio products. You'll get much better value if you stay away from the gaming brands, unless you find them at huge discounts (40% off or better, otherwise they're not competitive).