I had the front one go first, it was torn and I replaced it with SOS rebuilt one (the "stock feel").
Could not tell the difference and I can't remember how I discovered the torn one, I believe I was doing a clutch replacement.
Today, I would just fill the existing mount with urethane and be done with it. Cheaper, faster, and a lifetime fix.
It would be nice to get a poll of anybody with solid or urethane mounts. Is there any issue with NVH, metal fatigue and/or galled bolt threads?
NSX-R are stiffer? Part no.?