Click the link below. I read the comparison test in EVO this month between the Impreza Cosworth and the RS 500. Result? Impreza 31/2 stars RS 500 5 stars
The Impreza was suffering form an intermittent ECU fault but that only cost it 10 to 20 bhp and nowhere near enough to explain its poor showing. Looks like Litchfiuelds Type is still king of the Imprezas.
http://www.evo.co.uk/carreviews/evocarreviews/253273/subaru_impreza_sti_cosworth_road_test.html
Frawls
http://www.evo.co.uk/carreviews/evocarreviews/253273/subaru_impreza_sti_cosworth_road_test.html
Frawls