Some factory racks are complete crap. My dad has a chevy trailblazer, and to carry a canoe, he has to have a hitch-mounted t-bar to supplement the factory rack, as the factory rack can't handle the weight (it deforms terribly and looks like it will break the rack if used without the help). A good way to tell how good a factory rack is would be to check the Yak/Thule fit books at the store. If the factory rack option starts eliminating cargo options (say, ONLY giving a fit for carrying skis), then you know the factory rack is sub-par. Basically, the more options that lack a fit, the poorer quality the factory rack. It seems SOME companies have got the hint and no longer supply crossbars for their 'factory racks' or have started to contract out to Yak/Thule to produce their racks for them.