We have a 2008 Keystone Passport 280BH. It weighs 4508lbs dry (according to the scale at the dealer, includes appliances but not full propane tanks or battery). It has a 440lb hitch weight.
Loaded, I estimate it weights 5500-5700lbs. The axles max out at 6050lbs, so you can't really go crazy loading it up, but we find it more than adequate.
I've borrowed it to my brother-in-law, he pulled it with my Pathy. He said he would do it again, so at least I got that confirmation that I'm not totally nuts...
I also borrowed it to a friend. He pulled it with his dad's F350 Powerstroke. Didn't use WDH or anything, and he said he couldn't even feel it back there. With the Pathy, you definitely feel it. But I think its manageable.
With your V8, I think you'd find it no problem.
http://www.rvguide.com/specs/keystone/t ... 280bh.html