I've never used a bunk trailer, but I'm pretty confident that rollers won't do much damage. Been sitting on the trailer for 20 winters (that's mid oct-early june, and a foot or two of snow on the tarp) without any noticable damage. On power loadings, I'd just recommend that you don't pretend you're James Bond. I once watched a smart man get confused about his identity, misjudge the current, and ended up parking his boat next to his truck on dry concrete ramp. I think the trick is to keep it under 30 mph.