Finally installed it, hardest part was that my arm doesn't articulate very well to pull the old one out, but not to horrible. So, no big improvement noticed, but the engine does seem to be a little smoother. I think my old one was geting weak or worn out, whatever. I installed the sshpx mod 3 weeks ago and wanted to let that settle in before I switched to the grey one so I would know what did what. hpx is a huge improvement for me, and the grey cps seems to aid in the smoothness. I guess for $25 bones it was worth it for me. Now I want to see what DP-TUNER has to say about it. Just my thoughts everyone.