I changed my belt out on 07 700 efi at roughly 1500 miles. Everything looks good except for considerable amounts of belt dust.I replaced factory oem with dayco hpx at that time. I most recently pulled belt cover off some 1500 miles later and noticed the lack of belt dust and how clean it was( Rollers ECT). The after market belt is like new. The clutch faces look stellar! I would have to conclude that the relatively cheap Dayco belt stands up much better than oem with no downside! I recently purchased new primary c/w stages 1,2 . I did notice that the oem belt is much softer therefore bending Much easier than Dayco with aramid cords. I am wondering if i would be better off using oem in this app. due to extremely tight radius on new machined primary. Would be interested to hear from anyone whom has done this upgrade! Thanks!