I use the Respironics Synchrony ST BiPap. The ST version is more sophisticated (and $$$) than the standard BiPap as it serves as a mini-respirator.

I feel very fortunate that UA was my preferred carrier at the time I was diagnosed. When I read about other airlines and their rules and restrictions I am so very happy to have the UA AeroMedical Desk to take care of me. Granted the extra steps of having to get on board early, educate the flight crew, and check to make sure the power is operating properly while the mechanics are still there is a pain, but in the end it's all worth it.