From the pictures Ive seen they have only three bolts holding the gear in place. With only three there is a greater chance of them slipping which could result in bent valves. I myself have aem another three bolt design I wish I didnt buy them because of that (but hey they were only $50). You might want to try the skunk2s they are six bolt design and cost about $200 for both.
HTH
KJ
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Objects in mirror are losing.
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Don't bother giving me "rep", I won't return it and I think it is stupid.
Gracie Barra Clearwater
Gyms in Clearwater, St. Pete and Port Richey
pm me if you are interested in trying a free class at any of the gyms.