Well based upon my research it seems that transmission and engine mounts will have the biggest impact on NVH and subframe bushings not so much.
But I'm hoping to get first hand input from someone who got these solid bushings.
I want to improve rear end stability and grip for the most.
Another reason is that the M3 subframe bushings have induced or amplified some weird resonance noise. This does not happen on alot of cars but it did on mine. So getting solid mounts may get totally rid of this, or make it worse than hell
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