Personally I don't believe I will ever need another sleep study. I get more feedback from my auto w/software than I got from my sleep study. With it my pressure is always being reevaluated. I have found that my 90% seems to change quite a bit, although I believe the long run average would still be at my original sleep study titration of 11.5. Last week it was jumping back and forth between 11 and 12. But the last two nights I have been dreaming like crazy and my 90% went up to 13, my maximum pressure setting, and my AHI went from the lower end of one up to three. Even so, I'm looking forward to more of those dreams tonight . Two weeks ago I came home totally exhausted and sore from a hard day at work and was concerned that I might have a bad night as a result, turned out I was wrong. My 90% did bump up to 12 but my AHI dropped to my lowest yet of .4. My point is that for me the constant retitration I get from my apap seems to flo very nicely with my current mental and physiological states. Given the data I've been seeing I don't believe that the original suggestion of cpap at 11.5 would have been as completely adequate as my treatment with an apap. As pointed out by many others here I also think that with the majority of cases money would be better spent by purchasing an apap with software. Of course I am sure that there are other cases and symptoms that would require additional sleep studies due to the limited feedback of an apap. And of course an apap may not suffice for someone in need of a BiPap. But for me, I'll just use that sleep study money to buy my next four apap's. Well, that being said, it's time to muzzle up and hopefully have another three point night, so I can see if that hot blond is still waiting for me up on the ski slopes . --- BT