I don't have a data capable machine. I also want to have a back-up CPAP "just in case".
Therefore, I'm going to buy a data-capable machine.
Looking around, I find that I can get a good price from SecondWindCPAP.com for the DeVilbiss AutoAdjust machine with a data capability. Total price: $570 AND a three-year (not two-year) warranty.
It's a nice machine with simple data. I have 2 - the Intellipap and the Respironics System One. I use the Respironics at home which gives really detailed data, but take the Intellipap (named Sleep Cube in the UK) away with me as it's light and compact and can get simple data easily online via cpap.com or the devilbiss website.
You can get a data capable machine for less than that. Check out cpap.com, and check out the Respironics System One DS-150HS cpap. It is simple, and has data backup capability through a SD card and a 6 month internal memory.