4.9 to 60 for the STi, 6 secs for the M3. M3 does feel a slightly quicker over 100, but that could be decieving. Don't forget it's an everyday car aswell. If it were purely for the track the Impreza would win hands down, but considering it will spend most of its life on the road the BM looks the better choice but who's to say it will stay that way. The Impreza would be very simple to get more horses out of should I get bored