I'm going to put flat bars on my Centurion single speed conversion. I tried the flipped and cut bullhorns yesterday for about 12 miles and the position is just too low for me (the saddle is a fair amount higher than the bars). I couldn't get comfortable, and my legs were cramping from being hunched down over the bars like that. So, a riser stem and flat bars are next for it. I know people say they don't offer as many positions, but for me they are so comfy that I don't *need* any more positions.