The dia-compe 990's are a very powerful brake if you know how to dial your brakes well. They have some donwsides though... The pads dont have threaded posts and they are a bit tricky to get dialed perfectly, but once you get them they should stay good. The stack hieght is higher then most newer brakes so if you run CS mounted brakes and a small gearing setup then they may not be compatible. They are cheap though and Id say definetly worth the money, as when they are set up and dialed properly they can out-perform most brakes on the market