It's going to depend a lot on your use.
I usually set up a base camp for anywhere from 4-7 days, and having the RTT on the trailer works out great for that.
If you tend to move around, and not spend more than 1-2 nights in the same spot, then an RTT on the rig may work better.
I've only found one trail where my trailer would have been a hindrance, and that was 'Black Bear Pass' in CO.
Although, in places like Moab, I set up my trailer as basecamp, and take the tow vehicle out to explore/trail ride.
I also need the extra room of the trailer, as my TV's are a Jeep TJ or my CJ, where space is at a premium, especially if my son/dog/wife/all 3 come with.