On my Pontiac the crossbars were fairly strong and the siderails were massive so I never worried about tossing anything up to and including a small sailboat up there. Now I've downsized a bit, the new van doesn't have the side rails but the crossbars are very stiff and removable; the attachments are really heavy duty, I remove them for the Winter - 5 minutes, no tools - to make cleaning off snow easier. Clever design, but I miss the side rails which were so great for tying down to. Hard to find a good spot to attach bow and stern lines - I'll have to fabricate something.