Ya, the Limit is a nice feature, there is a slight lag in the head position calculation that is unnoticeable except on an over shoot when looking back and over shoots the 180 deg. The limit fixes that. I don't use it on the pitch curve since looking up is not as fast of a head moment as the yaw movement.
I finally have my looking back squared away. The X curve seems to be the key there.
I tried to use the speed cure to slow down the fast moving head but found out that use the profile curve first then use the speed curve to fine tune.
I have not tried the hat clip yet.