Ok, I just finished the tranny fluid swap and went for a drive. Like what I have read from many others that did this with the MS3, the gear shifts are much smoother now. I have also been told that the synthetic frees up HP and increases gas mileage. I'll learn more tomorrow morning when I go for a drive with the tranny cold. I have been having hard 2nd gear shifts when the temps are very low. I did this in my 1997 Probe GT and cold morning 2nd gear shifts were greatly improved. I was using the penzoil syncromesh in the Probe.
Even if I still have cold morning hard 2nd gear shifts it was still worth doing. It was not any harder than changing the oil, no way I would pay someone to do this.