I talked to Jared about the rb6 this weekend at the Missouri state finals. He ran the clamping front hexes and axles with the caster inserts set to a shorter width, but still ran the RB6 suspension mount. He did not run aluminum hinge pin mounts, the new ones are stronger and so are the rear hubs. He also ran .5* hubs at WCRC nationals because the track was a little loose. He also ran the original RB5 flat 521-1 arms with one hole. He said he does not like the feel of the gull wing arms.