I am considering one as well. Would be my primary driver as well. I shouldn't have sold my Armada when I sold my race car - in less than 1 year here I am picking up another race car!! I drove one and they are real rocketships and very manouverable in parking lots and so forth. My biggest concern is the drivetrain - mostly the diffs. Some are having trouble with those already, and other high HP cars besides the Vette that GM has produced seem to cut corners in that area as well. Motor and tranny are pretty robust. I am thinking it would be smarter to wait until next year and get a '07 model with the 5/100K drivetrain warrantee - that would help. But the prices now are tempting ~$33K for a fully loaded LT with Nav that stickers for $40K.
Others I am considering include: Touareg, 4Runner, Land Rover LR3 or a more traditional approach like Exp, Tahoe, Yukon, Navigator
My tow set up is ~5000lbs so could push over 6K with tools, cargo and people. I also need a AWD for ski season.