1/2 sec = 0.5, correct? Well, the SI runs 15.0 stock (if all goes well), so that means a WRX runs 14.5? Back in 2008 maybe. 15.0 is not fast by any means, at least not by modern (last 10 years) standards. I don't think those POS Si'ssies run low 14s with bolt-ons.
The honda civic Si has never been fast in stock form in US released versions. 15s in stock form is not 'fast', but rather 'tolerable' unless you're in your 50s with the beginning stages of arthritis. Half a second in 1320 ft is a huge margin as well. That's like saying the Cobalt SS (14.0) is just a little bit slower than the STI (13.5).