When I first put on my progressive link, I am sure I could feel a little vibration in the floorboards, but it went away after just a couple hundred miles....don't know why, perhaps things were slightly out of alignment and then settled....I don't know, and I never checked the alignment before or after installing it. I think that all the stabilizers basically do the same thing, which is to reduce pure sideways movement of the swingarm....pick your design, I like the price and simplicity of the progressive version. And it did tighten up the chassis considerable. You can still feel a flex in the chassis, but it settles immediately, i.e. just one time versus continuing to wallow as they will do with nothing. Having said all that, I also think that all the stabilizers are working on the symptom and not the problem. I think the problem is the soft rubber in the swingarm itself letting the swingarm flex too much, and not just side to side. So I am seriously considering also installing the Glide Pro bushings. And not because I even ride my King so that I need it, I just am struck by what I think is poor factory design and would like to fix it, even if I don't need it.