Thank you sir! Rotella is best! I like trials tires a lot, I think they are great, and especially when there's a lot of roots and rocks, they just do a superb job in that stuff as long as you run low pressure. When I do use one, I use dual opposing rim locks, ultra heavy duty tubes, and run about 6 lbs of pressure for best effect. They require low pressure to work, they don't work right if you run the normal 12 lbs or so that you would put in a knobby. I don't think they really suffer in sand or regular soil much, but no real advantage there, either. And in mud and muck, they don't do so hot. I do have a spare set of wheels and I keep a trials tire mounted on the rear of my spare set, and put it on when I think it will do well. But if there's an MX track component to the race, or if I don't think it's going to be too rooty (haha wishful thinking in most cases) or rocky (probably only two venues so far meet that description) I will put on a regular knobby. Not that it probably matters a whole lot, at my level of racing, probably just about anything will work, but at least in my mind, by doing that, I sleep better knowing I've given myself every advantage that I can control. But in the end, it probably doesn't really matter too much what I run, whether it's a rounded off old knobby, a fresh one, or a trials tire. I seem to ride about the same either case.