I have the Diamond Power Sports and I HAVE tested them out at @ 30 mph. Mine measures 4" from where it touches the metal to the end. It was ground down a little over an inch and completely saved my plastic. I immediately replaced the one I screwed up. I think I paid @ $60.00 for the pair, so they paid for themselves a few times over in one accident. I have heard both positive and negative regarding the longer length. ??? It will save all of your plastic in a tip-over and it worked great for my slow speed low-side. I have heard bad things regarding the "no cut" sliders, but have no experience with them. I guess you have to gather as much information as you can and make your own choices from there!