Amazing the long lasting untruth that Bilstein sports are shorter. Right now I have a set of rear HD and sports and they are the same length. The sports are stiffer and have 5 instead of 3 spring perches. I have the front Bilstiens that came out of my Euro 535 and some sports, and the sports in this case are longer and stiffer. Of course this could be debated but I have had many sets on the floor at once and am here to tell you they are the same length. Don't take my word, check with shox.com. The 535is had the same size sway bars as the regular 535 and the M5 had much larger bars.