This is by far the best mod I have done. It is a pain getting the M3 boot seperated from the plastic frame (much harder than the M5 boot), but definitely worth it. Thought I was going to tear the leather a few times, but just need to be patient. Used needle nose pliers to seperate once got a smaller corner started. Also, didn't need to cut M5 boot, just cut holes for clamps to peak through.
All the M's I have had, couldn't stand the throw. This shortens it up and like the weight. Concerned the shifter was going to be too short, but it is perfect. No issues.