We bought a Westmarine RU-250 rollup and want to cruise with it inflated. I was hoping to just use some ratchet straps to hold it down. The bow seems ok when we thread the ratchet straps through the port/starboard rings attaching to the rooftop bars. Because the inflatable is much wider than the roof racks the stern section with ratchet straps does not hold centered very well. What are you guys doing to hold your inflatable down during transit? I posted a couple pictures under my profile in an album called dinghy. Thanks for your tips!! Sean