What spec. system would you recommend?

I was recently diagnosed with OSA (AHI=45) and need to decide on the type and brand of a CPAP/APAP machine and mask to purchase. Can anyone please share their wisdom as to what they feel is the very best brand and type of system as well as the most comfortable, quality brand of nasal mask/pillow?

a mask is very specific to you and your face... generally no two people are sold on the same mask. Best thing to do is to find a place that will let you try a bunch on (check with your sleep lab).

a machine? 3 choices... Respironics auto (either with AFLEX/CFLEX or straight CFLEX), a Sandman Auto or a Resmed Vantage (either version 1 or 2) any of those will be good... depending on your pressure.

a humidifier... FP 150... which will work on any of the machines listed above.

Software for the machine that you pick.

I'm partial to the Resmeds for their ease of access to so much data via the LCD screen. I'm intrigued by the new Covidien Sandman Auto and the DeVilBiss AutoAdjust IntelliPAP. I'm not a fan of the Respironics M Series but have bought and do own a Respironics pre-M Series Auto w/C-Flex. Other than the fact that the Sandman and DeVilBiss don't offer any form of expiration pressure relief (which not every one needs or likes) you will get excellent therapy w/any of the above. The Respironics M Series came out in 2006. The Resmed S8 II AutoSet, the Covidien Sandman and the DeVilBiss AutoAdjust all just came out this year (2008). All of the above are fully data capable and have software to download the data.

As has been mentioned masks are a very individualistic item. One man's poison can be another's ambrosia. That being said the new Swift LT appears to be quite popular and well-liked in nasal pillows style. The Quattro seems to be fairly well liked in full face mask style. There's a real wide array of nasal cushion masks and I'm not familiar w/the various "hybrid" styles such as the Liberty.

Mask... a lot depends on whether you tend to mouth breathe during sleep. Might need a Full Face mask for that, rather than another type. And, as cflame1 pointed out, masks are a very individual thing. Best to try as many as you can in actual sleeping conditions at home. Easier said than done, of course, since masks are expensive, and the DME might not want to swap many times (if any.)

If I needed a FF mask, I'd want to try these first: ResMed Ultra Mirage FF and Quattro.

If I could use a non-FF mask, I'd want to try these first:
nasal pillows mask - Aeiomed Headrest, ResMed Swift LT, Respironics ComfortLite 2.
nasal mask (covers just the nose) - ResMed Activa, Somnotech Soyala, Puritan Bennett DreamFit (not to be confused with the "Dreamseal" attachment for PB's Breeze.)

Machine... depends on what pressure you're prescribed and how easy/difficult it is for you to exhale against the prescribed pressure.
High pressure prescribed, or difficulty exhaling and a prescription for "CPAP" -- I'd want the Respironics Auto with A-flex or ResMed S8 Autoset II.
Difficulty exhaling and prescription for "bipap" -- the Respironics BiPAP Auto with Bi-Flex.