Getting my Camper installed this Tuesday ... Hooray! After I get solar installed I will be looking to complete my Yakima Rack System. I see three crossbar choices, if I am understanding this correctly, Whispbar, Corebar & Roundbar. FWC crossbars, from pictures I have seen, look like Roundbars. Can the installed FWC Yakima tracks handle any of these three crossbars? I ask because I have Thule “J-style” kayak mounts & Thule canoe mounts. Anyone out there with a preference and why? If I am being clueless, give me a quick explanation & detention.