I'm not telling him what frame to buy, my point is that a frame size difference is no big deal which it isn't if his range is 54 / 56 or 56 / 58 I don't know but if he's close, he won't have any trouble tweaking it. I ride a smallish frame 54 (I'm 5'-10") but I also have a 130mm stem. I could have gone with a 56 cm frame and a shorter stem and been fine but like I said it was a wheel issue at the time.