i ride a 52x16 on the streets here in LA and i have no real issues with it. I was running a 44x13 (had a cassette on it before) and this gearing is a little bit nicer. I find the knee issue to be more how you are riding and not so much the gearing. When i went to SS i was on 44x16 and i was spinning out like crazy. If i kept that gearing any longer i would have grown some calluses on my ass from bouncing around so much on the seat trying to keep up to speed. I guess its all personal taste, i like smooth cadence and going fast on flats than winding out on flats which is 98% of my daily ride.