Just did this mod on my 1M. Everything went smoothly.
The original transmission mounts definitely feel alot softer than the E46 M3 replacements. I haven't driven the car yet, but I didn't notice any extra vibrations or noises when I moved the car off the ramps and back into the garage. I'll give some thoughts on how it feels once I drive it a bit more.
Thanks to wolfe for the DIY.
