I'm trying to decide on going clipless or just buy new platforms for my SS Trek 4500. I have a pair of 661 clipless shoes already. my budget is small ~$30. What I want to know is if anyone has had a problem with cheap clipless pedals on a mountain bike. I would like to get some egg beaters or maybe ATAC's. I have read some bad things about cheap SPD's. Thanks for any input.