I tow a goose neck car hauler and have an Access Roll Up cover, I'm very happy with it, it only takes 10 seconds to roll it up for towing and once I drop the trailer 10 seconds to cover the bed, the cover is very water tight and looks good, the bows roll up with the cover, the cover can be locked (allthough not as secure as the aluminum roll up covers) but it also takes up no room in the bed like the aluminum roll up covers do.

There are pictures of the cover on my web site (in sig. below) "click" on the aftermarket options link