Well I just had the STI STS installed in my Legacy GT LM today. I drove about 600 miles on the stock shifter just so you all know. Anyways some of the things I noticed and didn't like about the stock shifter were.
1. The shifter shaked a lot, like wobbled back and forth, side to side. I know some other people here were complaining about that too.
2. The shifts were to long and soft for my liking, I needed more feedback as I found myself gringing gears when shifting. something that happend very rarely in the 2 years driving my WRX happened more times in 600 miles driving the legacy.
So after getting in the car after the install I noticed the difference right away, shifts were much shorter. It was much more persice and solid feeling, like the way it should have been from the factory, not all wobbly and soft. It no longer shakes like it did before either
So overall I would give it a 92%, its a little notchier but I can live with that. So anyone that was thinking about getting this and wants a more sporty drive, deffinetly get this. If you think the stock one is fine, and like the luxury more then the sport of the car, then you might want to stick with the stock one.