Aside from solving clearance issues, wheel spacers push the stock wheels out far enough to "fill out" the wheel wells, widen the stance and give the truck a subtle yet very noticeable more aggressive look.
I'd pony up for some spacers and go 285s. I ran mine with the toytec ultimate, 287-70-17s, and either 1.5" or 2.0" (cant remember) AllPro wheel spacers for a while. Had no UCA rubbing issues. Had to trim the piss outta the fender liners though. Only reason I stopped using wheel spacers was because I put on aftermarket wheels, then upgrade the UCAs after the fact.