These guys are awesome!! I bought a used MTB for my wife. The lady I bought it from must have taken it home from the store and just left it outside. These guys fixed it up like brand new!! and a super reasonable price!! I always use these guys - super friendly and can get you any part you need.
Before you buy a discount store bike, check out the used selection at the Re-Cyclery, you'll find a much better quality bike for about the same price you'd pay at the big box store, Check back often, cause the selection changes all the time!