At the time of my purchase, the turbos and superchargers for the G37 were in their infancy. Now that big names like Stillen and GTM have refined the aftermarket forced induction for the G37, it would be a worthy 335i contender. stage 1 is 420hp and stage 3 is 550hp. It would definitely give a tuned 335i a run for its money. Dyno chart in the link below is interesting.
http://myg37.com/forums/engine-drive...s-release.html
It's a nice car and I see much more 3 series on the road than the g37 in Chicago.