How prematurely?
Mine have been on for over 8 years (62,000 miles) of what I'd call 'leisurely' driving.
How prematurely?
I have a suspicion that you will like the 034MS mounts. It won't be as stiff as the VT mounts, but not as soft and spongy as the OE either. NVH will be eliminated (at least for me) at idle.
i think i was one of the first that had these mounts and i actually tested the road and race versions for VT... i kept the race ones and sold the road versions. ive found these mounts to be absolutely excellent and in my application they've been put through ALOT of stress , not loads of miles but a whole heap of heat and twisting with a sprint track mostly use. I'm going to have a detailed look at mine this weekend and see how they look and report back.