According to the sticker on my frame, I'm borderline for frame size. If you go by the height listed on my license (5'6"), I should be riding a small, which in Giant-land is 46cm. That would be an absurdly small bike for someone my height. Giant recommends the 50cm to those 5'7"-10". I think the reach may be a hair long, but I think the reach on the smaller bike would be short.