I trailer my ten foot steelheader guide model. Your right, it is a much less painful trip if you set up at home and then just slide into the water once you get there.. As for the trailer, I personally have a 10x6 flat cedar decked olympic that I simply use cam straps to secure my cat. I bought it in olympia direct from the builder for like 875 bucks they were willing to make deals... The highway is fine as long as you properly secure your cataraft. Its also important to make sure that the manufacturer of your trailer uses the proper bearings that can handle the heat of long road trips...Always ask about the limits of their bearings. Mine came with a 3 yr warranty. Hope this helps some.
Drew