Originally Posted by
due ruote
People tend to migrate to larger frames as they age. If both fit now, the 55 is likely to fit you longer.
For some of us, our doctors say we are smaller than we used to be. FWIW, I have a smaller frame or two than I used to ride. I like the smaller one(s) as well as the larger ones. And the larger ones don't feel as big as they used to be.