I have a 2002 GMC Envoy, which as you probably know is the same truck, same engine, drivetrain, etc.
It pulls pretty well. I have the self-leveling suspension (Basically air suspension in the back that keeps the back end from sagging).
It has no problems on the ramp, and I can cruise about 80 on the highway with not much trouble. I have smelled a little something when I trailer at high speeds for more than 20 miles or so, but hasn't really hurt the truck from what I can tell. It has 95000 miles on it, and I have been towing with it since I bought it.
By the way - I have a 2000 Mastercraft X-Star with Single Axle.
(and before anyone blasts me for going 80, I know its not the brightest idea to go that fast - thanks. But I never claimed to be the sharpest tool in the shed.)