9668 is lighter, has way thicker pads, comes at a lower price for the same quality (Brembo GT line requires the GT-S caliper to be comparable, maybe even the GT-R), and has way easier pad changes. I also find way better documentation around AP Racing calipers.
I just don't like the caliper as much. I see a lot of people on other platforms run the 9668/9660 calipers and they absolutely love them.
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@stupidtoycars | My track vids
09 7AT|MCS 2WNR|Topgunz Rotrex|Ecutek (Eugene)|Maxxis RC1|Titan-7 TS-5|OSG LSD|Rear Mount Derale Oil Cooler (WIP)+25 Trans Cooler|Fismo|G-LOC R12/R10|Zeta III L|NLR Wing and Splitter|CJM Pan and Fuel Hat|Radium Surge Tank|AP Racing CP9668
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