2011 Chevy 2500HD with the Andersen hitch, under bed gooseneck, we did 2500 mile trip last summer after getting it setup no complaints. The pros for me where price and the fact I can take it out by myself when not towing and put the bedliner back in. Takes me 5-10 minutes, so easy!
My trailer is 8' and I can get 90 degrees. I rotated the adapter and use a 5" offset because that's all Draw Tite offers. Unfortunately, I can't remember how much it clears by.
To the OP, this is my first fifth wheel, and I researched hitches like crazy, good luck, there are many great hitches really comes down to your personal needs. You might want to buy the trailer first, you could always have it delivered and then install the hitch.