We switched from a truck to trailer probably 20 years ago now.  Not really apples to apples since he truck was about a 1972 and the trailer was brand new.  It is a minor pain to have to get out and manually pull the lever both ways to dump and put back down and basically eliminates dumping and driving.  Also the much lower ground clearance is a problem for dumping repeatedly in the same spot, very hard to get a good high pile.  Instead you just make a windrow.  For our occasional use the trailer works fine, if we were hauling stuff a lot and dumping I think a truck would be better.  Ours gets used more to haul machinery around than as a dump truck.