Brad, First- let me say that I sell Renegade and United Specialties, I used to sell Haulmark and I have had all three as demos. I drive truck conversions about 20,000 miles a year.
The 6 big manufacturers- (Renegade, Haulmark, United Specialties, NRC, Showhauler and Optima) all put out a very nice product. If you want to customize, stay away from Haulmark. NRC, Renegade, United Specialties and Showhauler will build a custom floorplan for you. NRC really dolls the interiors up if you like- very nice, but you pay a little more for it. Showhauler and United Specialties seem very similar with a nice amount of options and interior selections. I have had good luck with service on our units, a few more small problems and problems with customer service on the Haulmark.
This is a very big investment. I would highly suggest taking a factory tour- I think most of the manufacturers can accomodate you if you give them some notice. You should be able to see all except Optima in 2 days in the Elkhart- Bristol Indiana area.
Bob