I was about to build a P4 with a durace7950 compact(50-34) . The gearing is all I need but I am concerned after reading problems with a compact on a P2 and also trouble with shifting on the P3C with a compact when I did a Slowtwitch search.I hate bad shifting and am OK with a 53-39.Is a standard crank the only way to go on a P4 so that one has optimal shifting?