Might not even be launching off the trailer, just using it for road transport and line up with all the other yachties at the crane come springtime. Mind you the previous owner of the trailer did launch his yacht off it, but that was in a lake and using a tractor.
If I do launch off the trailer, I'll need to have total confidence in the vehicle, an excellent slipway, and plenty of time, I only have to do it once a year, afterall.