Coming from the street scene, 240sx's and M3's, most of the time slotted is the choice and they stay away from both cause as Matt said most of the time its just marketing and appearance people go for them.. Most applications slotted give the best performance. I never considered what would happen when wheeling but I always clean the s**t out of the suspension and around the wheels anyway, Im actually looking into the Stillen front/rear set-up as they've gotten great reviews and have option for zinc coating to stop rusting..