Back in the 1970's, nearly every farmer around here had a 2 ton truck. Most had a flatbed with a set of grain sides and a set of stock racks - used that one truck to haul everything. Some of the nicer ones had hydraulic dump beds - if not, most of the grain elevators had a hoist that you parked the front axle over and it would lift up the whole front end of the truck to dump the grain. Somewhere in the late 70's round balers and gooseneck stock trailers started getting popular, and then came grain carts and belly dump semi trailers, and the old 2 tons all faded away. Like most everybody else, I wouldn't want to go back to 'em.
The other thing that we had back in those days was almost every set of pens had a ramped loading chute. They faded away too - now the only ones that do are the ones set up to load pots. Unless all you ever did was haul from your own farm to a sale barn, you'd need one of those portable loading chutes to pull around behind you everywhere you go. In this part of the world where almost every cattleman has several different places scattered around with cattle on them, that would get old pretty fast.
As far as legality goes, there's probably not a whole lot of difference if gvw's are equal, but I'll bet (around here at least) you'd draw more attention from the DOT than a pickup/trailer combination...
