I put my 14' 6" Sotar and everything that goes with it on a TopHat trailer. I bought it up in Cheyenne from these folks: Factory Direct Trailer Sales
TopHat is better quality than any other trailer I've seen hauling a raft. A buddy of mine did pretty extensive research and ended up w/ one. After I looked at about 3 places in Denver for comparable quality to his I gave up and asked him where he bought his. It was cheaper than the flimsy pieces of crap I found in Denver so I drove to Cheyenne and bought the same one he has.
Real 15" rims on a real axle with real tires. Solid construction. Rides great empty or full (I got one w/ the axle centered front/back).
Mine came with a pine deck and steel frame sides and I used 2X6 cedar to put siding and a tailgate on it and capped the tops of the sides w/ strips of Trex Dex. I had a friend weld a spare tire holder to the front (that shop in Cheyenne will do that kind of thing for you). I mounted 6 massive D-ring cargo tie-downs to the frame through the deck. You could lift the trailer w/ one of the tie-downs. I probably have about $1300 in it (their prices have gone up since I put mine together, I think my base trailer was about $900 something and is now over $1000).
I don't see how folks can be comfortable hauling a full load on the tiny little wheels and axles most utility trailers have. They look like junk to me and they make me nervous when they are in front of me on I-70.