Do you expect to get an objective answer to that from a Red Hat list? Most users on this forum are familiar with GFS2, some may have tried OCFS2 but there's bound to be a bias.
GFS has been extremely stable for us (haven't migrated to GFS2 yet, went into production with GFS in 2008). Just last night in fact a single hardware node failed in one of our virtual test clusters, the fencing operations were successful and everything recovered nicely. The cluster never lost quorum and disruption was minimal.
Performance is highly variable depending on the software application. We have developed our own application which gave us freedom to tailor it for GFS, improving performance and throughput significantly.
Regardless of what you hear, why not give both a try? Your evaluation and feedback would be very useful to the cluster community.