I spent alot of time at the track watching people with their NA Mitsu Eclipses spending money on turbo kits,carbon fiber hoods,lighter flywheels,etc and couldn't even touch a mildy modded turbo model and with an AWD version they wouldn't even be close and for all thnat money that could've had the better model and be quicker and better all around.
I'm just saying buy the higher horsepower model within your same car model and save a bunch of money and compete outside you class. Me personally I couldn't just pour money into my Focus just to sniff a stock ST's butt but I guess if the individual isn't trying to overachieve then have a ball but from a money standpoint it's not the smartest route.
'12 Focus Red Candy SE Sport 5 spd
'99 Toyota 4Runner Sport
'11 Subaru WRX STI Hatch