Autopap.
I've used autopaps from all three major manufacturers. Not because any machine went bad...I just wanted to try all three, with their software. All three treated me well:
Puritan Bennett Goodknight
420E Auto - Silverlining software
Respironics
REMstar Auto with C-Flex - Encore Pro software
Also had a REMstar Auto before C-Flex was added to REMstar Autos.
ResMed S7 Autoset
Spirit - Autoscan software
Have also tried 3 Bi-level machines:
Respironics
BiPAP Pro (unfortunately, wasn't a BiPAP Pro
2, so there was no interesting data to view via software.)
ResMed
VPAP III - ResMed's name for their bi-level machine.
Note: Bi-level machines are often called "bipaps" although "BiPAP" is really Respironics' trademarked name for the Respironics bi-level machine.
ResMed
VPAP III STA - bi-level with timed back-up "breaths" available, if needed, when operated in "timed" mode.
The bi-level machines also treated me well, but I much prefer autopap.
Gee, what a ridiculous hobby of sorts this treatment stuff has become for me!
No, I didn't buy all those machines!! Some were loans or swapping with others just for the sake of trying out another machine.
P.S. Straight cpap set at about 11 would treat me just fine.