The GT500 top mounts are slightly better than stock but still wear out about the same with track abuse. I really need to upgrade to CC plates but I've been too cheap up until this point. I think for street driven cars, they are great replacements, though.

 

This.

I am running Koni STR.T's and Steeda Sport Springs w/ the Steeda HD mounts. No problems, easy to set hot swap points at the track and set them back for the ride home.