We debated the same thing 4 years ago. After much debate we decided to go with the 5th wheel.
Four main reasons were.
1. Very stable in high winds.
2. Easy to hook and unhook.
3. High ceilings give a very roomy feel.
4. Lots of basement storage.
I think the deciding factor for us was a friend that owned both said the 5th wheel felt much more stable. The dealer also said if we don't stay in one place too long the 5th wheel would be easier to hookup and go. We have done many long trips where we only stay 2 or 3 days in one place. The 5th wheel just seemed to work better for us.
Good luck.