Had a 2006 Mtn Apex that I rode for 300 miles before adding the supercharger. I also built a sled for a customer using a 2006 Attak and stretching it to a 151" sled.
2006 Mtn Apex
-Clutching
-Performance Lite Seat
-Performance Lite Exhaust
-Ran stock, Simmons, and Slydog Powderhound Skis
-Pros: Great through the fluff and climbing
-Cons: Tougher to boondock at times
2006 Attak 151"
-Hartman Inc long track kit
-Clutching
-Excell Motorsports
-38" Mountain Ski Stance
-Ran stock mountain and Slydog Powderhound Skis
-Pros: Great through the fluff and boondocking or tight technical riding
-Cons: Was usually 10-20' shorter highmark compared to the 162" Apex Mountain
My personal preference was the long tracked Attak. It just worked better for most of my riding and handled better in the technical riding for myself.
Pictures of the Attak 151" sled
http://www.totallyamaha.net/forums/showthread.php?t=18657.
This coming season's project is a Vector Mtn SE with supercharger, light weight hood, light weight seat, Excell Motorsports high flow header, Slydog Powderhound skis, clutching, and light weight rear and front skid.