FCM shock mount kit

[PhilZ]

I am looking at this
http://fatcatmotorsports.com/FCM_MCU_mounts_NB.htm
which appears to be a hardware up grade has anyone use these?

"Our hugely popular and effective FCM MCU shock mount kit is now available for 1999-05 Miata shocks!
Proprietary MCU bushings and custom mounting hardware replace the traditional factory rubber bushings with a
higher-quality, more durable (5 times longer-lasting), and more vibration-absorbing alternative.
Ride quality will improve and you'll also gain suspension travel when using FCM bump stops.
The FCM shoulder nut is specially designed by us and is made to work on NB (99-05) shocks.

This kit may be used with any shock designed to fit the NB Miata, such as Tein Basic, SS, Flex, Monoflex, JIC, XIDA etc. "