I'm riding a mountain bike with slicks and road pedals. I have slicks on them that have a mild tread on them. Saw some slicks that were actually um slick -- as in no tread -- at the LBS ($50-60 for the pair). Wondering since I'm pretty much using my bike for road rides only now if I should change to less tread? Does it make a difference -- better, worse? Anything else I need to know? Thanks.