We've pulled both, and much prefer our fiver. Reasons are as follows in no particular order...
1 - Much easier to pull, with no sway or 'push' from passing trucks or side winds.
2 - shorter overall length as the front extends over the bed of the truck.
3 - Much more storage space in the basement, although that is somewhat offset by space in the truck bed that is lost to the hitch.
4 - A much more spacious feel in the coach with the tall ceiling.
5 - Separation between living/kitchen areas and the bedroom suite enhanced by an upstairs area.
Having said this, though, it is a personal decision. Some prefer not having steps up to the bedroom level. Some prefer to not have the need for a truck of a size needed to pull a fiver. Some might agree with my points above, but don't feel that it's worth it to them to spend the additional dollars for a fiver/truck combo. No right and no wrong... only what works best for you.
2008 Jayco Designer 35RLSA pulled by a 2007 Chevy 3500 D/A SRW