I currently have a 56cm Felt Z85 and a 58cm Scott CR-1 Team. I have found that I am generally comfortable on a 54-56cm frame, depending on the geometry of the particular frame. I got a great deal on the 58cm Scott and with a shorter stem and a few adjustments the reach and seat height is the same as my Felt. On the flats or down hill I'm fine on the Scott, but I've found that in a climb the bike starts to feel really big under me, even though, like I said, I've got it set up with a nearly identical reach and seat height as my Felt. Fit is important on a bike, but as others have already said bikes are adjustable within a certain range. I also agree that a slightly small frame is easier to fit than a slightly large frame. This has been my experience with the Scott. Ride what is comfortable. Don't just get something that is not the correct size simply because it is a good deal. I'm looking to get rid of my Scott for a bike that fits me now. Hope this helps.