Hi, The C hub is a stronger design, the pivot ball design came from onroad cars originally for quick suspension adjusting. It may work ok/good in a light buggy but the design blows big chunks in a bigger heavyer truck kit, it allows to much suspension twist compared to the C hub design which helps stop suspension twist. The pivot ball design also seems to have more problems in the long run with dirt/grime getting in the sockets binding up, making the suspension work less smooth. The C hub does not seem to have this problem.