[smart1]

Back in 06' and prior we used castors. The robot won't turn consistently because the castor wheels are always turning around, which to be fair in teleop isn't that big of a deal because you can correct the steering but in auto it is. I also know alot about castor wheels from 13 years of driving an electric wheelchair, I always have to correct my steering. You could use omni wheels on the front instead of castors to get rid of the unpredictability. I would advise against that even because you get pushed easily.