Thanks for the insight. This bike is my commuter so it will be on the street most days so maybe the shorter will be better. I have ridden both 170's and 165's on a different frame and it was just a matter of adjusting the seatpost height to find my fit. I have yet to venture out to the local velodrome because of sheer intimidation but maybe one day...which has brought on this deliberation about which length I will purchase.