I have to say that I personally would never buy a ProjectMix... they seem shoddily built to me, and if Pro Tools is the way you want to go, you should at least consider going for LE instead of M-Powered. There is some functionality missing from M-Powered that you may need, and that exist in LE.
I see the reason people want to like the ProjectMix; its a mixer/control surface with I/O and moving faders, etc... but after I demoed one I was disappointed in the build of the unit which seemed like a cheap toy.
If you can afford it, go for a 002R and get a Command 8 as your controller. The command 8 is compatible with all forms of Pro Tools including HD so if you upgrade in the future you already have a great control surface designed exclusively for Pro Tools. The only bitching I have to mention about this unit (the command 8) is that, for some inexplicable reason, Digidesign decided there should be 8 faders on the board and NO MASTER FADER!! whatsupwitdat??? There need to be NINE faders for this to truly be proper.....
Anyway make sure you demo before you buy. I have had bad experiences with just about every M-Audio product, and even though they are now owned by Avid (parent company to Digidesign) I haven't seen them stepping their products up a notch quite yet....