Let’s cut to the chase. Towing.

Not trying to bust your chops here Brian but you've got six pages of replies - some saying you're good and others not so much with a few on both sides providing real world experience to back up their comments. Will this dealer not let you take a test tow with the camper? If not, don't walk away - run.

I'm sure you realize this unit is at the upper end of the Tacoma's limits. As such, if I were in your position, I'd be basing my decision on my truck towing that trailer in conditions similar to those I'd expect to drive. A camper is going to depreciate even more than a new vehicle as soon as its titled so I wouldn't weigh any advice (probably including this) from a message board too heavily.

 

https://www.youtube.com/watch?v=qwFLOBrADBs

 

Pulling 6400 lbs on a flat bed trailer and pulling a 6400 lb TT are completely different. Wind resistance and higher center of gravity play more of a roll than the weight.