Seems quite new...
I watching these for a while, the KCA335 for the GC/GD chassis. I waited I think two years for these to become available for my GH8, but then WL had some problems with the 335 and suspended sales for a while. In the meantime I picked up some GRB hardened top mounts. Now these are available.
With the JDM GRF springs I use I'm just a little lower than stock and can only get a maximum of -1.0* camber. I never have liked the aftermarket camber bolt solutions out there.