What kind of 60’ times do you lay down?
His STI seems slow to me. Both cars on stock injectors he should have a massive advantage anyway you slice it. In any event, the regular WRX is a good performance bargain, and a fun car to drive, however to the OP is looking to buy a WRX with far more extensive mods than just an exhaust and a tune. Cars with those kinds of mods are the type that break trannies.