In the us there are no differences between the '00 and '01 rear section. Just get the '00 and you will be fine. As far as the difference between the STI and the scooby sport go. I would say build quality, sound and price. I believe the scooby sport is louder, and from what ive seen for the dealer optioned exhaust is cheaper. If I recall correctly the dealer option sti exhaust is just a brospeed or something like that, correct me if Im wrong.