I’ve been using a CPAP for about 4 years now, and it has really made a big difference. I used to get so dead tired in mid-afternoon, have no energy at other times of day, be very cranky, etc. My colour was pale.
My suggestion is to see if you can do what I did: try renting a different CPAP unit for a month or so; try each out and see which you prefer–maybe you don’t need one with the humidifier (heated or otherwise).
We’re not allowed to self-titrate here; only a technician can do this (and only then on the orders of the specialist MD).
I decided to not cheap out and get a really good machine–and I’ve never regretted that decision. I got a Respironics Virtuoso, which is a “Smart” CPAP, that self-titrates through the night as required (within a range limit pre-set by the technician).
http://www.respiratorycareinc.ca/SL_03.htm
It also keeps a record of hours used, and pressure adjustments: last time I took the unit in for titration, the guy downloaded the memory for the last three years, and printed out a chart, with every night clickable! (Not that I’m that obsessive, but pretty impressive!) I’ve dropped the thing 5 or 6 times, and it hasn’t stopped, and the casing hasn’t cracked or scratched. Took it to Britain and France: it has a built-in voltage converter! It cost me about $1600 Canadian (including mask, extra filters, etc.), which was mostly covered by my health insurance. I think the new model runs about US $700.
http://www.advanscpap.net/catalog/item/250192/176960.htm
You could also look at buying a used CPAP (with a new mask, of course!), to keep costs down.
But the big thing is to try the CPAP for a good month–the first few nights (or even couple of weeks) might be a little weird, and you might be tempted to give up–you’ll probably wake up in the morning a several times to find that you’ve torn the thing off in your sleep–but keep trying; it really will make a big difference to your life once your body has adjusted to the new feeling.