I traded in my '03 WRX for my STi on October 14th and I have been loving it ever since. There is just no comparison between the two cars.
I dont know who is having pinging issues but I noticed that the owners manual for the STi says that 93octane should only be used. 91 if you have to for a short time but dont push the car on that piss water.
Anyway, interior leaves me speechless. I am taken away to another world when I get in the car, every time I drive it. Torque is absolutely everywhere, 5th gear at 45mph and you can still fell it pull when you accelerate to shift into 6th gear. Oh yeah 6th gear gotta love that too

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The look, is perfect for me, exterior is aggressive(scoop and wing) yet still has some understated aspects. I love it.
Oh and handling is amazing as well, more solid than my WRX, and it had Tein coils with 225 40 nitto's
GO GET AN STi. People talk about boost spike, and ping. NOTHING that cant be fixed with engine managment in a couple months. And I have not experienced any of those problems. Just dont get a TBE and set a boost controller at some crazy setting like 17psi. In actuallity a MBC can aleviate the boost spike issues by acting as a boost-restricting device in the higher gears where spike could occur. OH and dont run 91octane.
Honestly, you will love the car if you get one. Simply put, there is nothing on the road in the U.S. that compares with it(even EVO, interior is crap compared to STi, and EVO has horrible paint). I firmly believe that once engine managment becomes available there will be no more talk of minor STi problems and more talk of mid-low 12 second timeslips.