I have no real experience of using these Trevor.
However, I would be inclined to avoid them, as stiffer bushes transmit more road noise[NVH] to the body and the cabin. Some of the Matra users put in Eurethane suspension bushes, and in a car that was already noisy, they created more din.
I bought the SVX as a luxury [read quiet] car that has a sporty nature, and I must admit I would not want to do anything to "harden" it. You have said you don't listen to music while driving. This indicates to me you live in a part of the world that has no traffic jams. Commuting in Dublin is about 30% driving and 70% sitting watching the rear of the stationary vehicle in front. So maybe you can see why I have a need for a car that is quiet inside and has a good radio.
Like yourself, if I am driving with purpose, I will shut off the stereo and won't even talk to passengers.
Joe
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