With all the different stuff you tow, I'd say keep the Dmax. Find or modify a TC to fit your needs for comfort and get a decent sized enclosed trailer to haul the off road Toyz when needed.
You could even flat tow a little jeep/ samurai so as not have to unload the camper if that's all your taking with.
And no way a 24k lb rig with a Ferd V10 is adequate in the CO mtns. My V10 pickup with a small trailer was wound out in CO. You'll want to kill yourself after pulling the first grade without the Dmax under the pedal!
