I run a B&W hide a ball with a gooseneck adapter on the trailer and really like it. Absolutely no clunking and still have plenty of room in the bed for anything else I want to bring along (firewood etc).

The only downsides I have experienced is it can be a pain to hook up compared to a 5th wheel type hitch just because you cant see it from the cab. It is also a lot more "flexible" than a 5th wheel hitch so you need to be more aware of the bed/trailer relationship to prevent any bed/trailer contact when maneuvering on uneven terrain.