We like our 2002 Keystone Cougar 278EFS. 6500 lbs dry and about 8500 gross and pulls easily with our 96 F250 with 460 cid gas guzzler. The trailer is 27' and has a nice floor plan with rear kitchen. In the past year, we got rid of the carpet and installed vinyl floor and I had a new roof installed by RV-Armor.com - comes with lifetime transferable warranty based on VIN so any future owners will benefit. I got rid of the sleeper couch and put a Lazyboy reclining loverseat in its place (found on CL for cheap) and added a residential queen matress (original mattress was no bueno...), oh yeah, ditched the Aqua Magic bucket and put in a Dometic 320 which is more in line with human anatomy. Last month I bought a Brisk II 15K unit and replaced the 13.5 as we are in TX and triple digits are the norm. The venting was in need of foil duct tape fixing to keep cold air from entering the ceiling void and I plan on tinting the windows next week. We like is cooooold as possible.
Older 5vers tended to be a bit smaller so look that direction and make one yours rather than spend buckets of money on a toy that depreciates faster than you can pay for it!