I use a 2003 Mountain Max at work and I think it is an awesome sled for what I do. I have reed spacers, dropped needles, taped the cab holes by the handlebars so it only gets fresh air, 2" risers, machined the helix and drilled the exhaust (don't tell my boss).
This machine rocks the house when crashing through the bush breaking trail and going through mega slush. Gas mileage is awesome for a triple two-stroker...I have reached up to 233 kms without running out of gas. I added gas before it ran out as a precaution so it wouldn't lean out. It's not a crazy fast sled by any means, because I have been out run on the lake several times, but it sure is fun to drive and easy to handle. Over 10,000 kms on it without a single issue. I just changed the sliders and they didn't even need to be changed. My stock Yoko 2" track is starting to crack and I am a little concerned it may blow up on me this winter...if it does, it will probably do so when I am at least 100km from my truck in the middle of nowhere by myself.
The only thing that really sucks on this sled is the stock mountain strap.