those tuffdesigns look pretty slick.
I have a cargomaster congo rack and basket. I like the functionality, look, and extra room, but I gotta be honest in that they really create a lot of drag even when not loaded. my mileage went to complete crap even when not loaded. just something to keep in mind.
also, it might make your rig too tall to get into garage, drive thrus, etc.
the previous poster's concern regarding higher center of gravity with a roof rack is valid, and the same could be argued for a rear bumper carrier...if you're headed up a steep grade it could in theory drag you head over heels. Just saying. don't do heavy crawling with either one.