I bought my truck used, and it already had a Truxedo LoPro QT installed. I hadn't had one of these before, but I would definitely get one again. They are a flat cover, so if something sticks above the rails it would be a problem, but I haven't had any problem with it. No problem at all with my 5th hitch. The thing I like the most, the cross stays are fastened to the canvass. So when you roll the cover up, it rolls the stays and all. Very easy to roll and unroll, no extra parts to store when rolled. It's the favorite cover I've had, and I've been driving pickups since 1985, and had many covers.
Mark