I would not trade just to get the power increase. BMW's are awesome to drive and you will miss it after driving a mustang daily. Get a tune and keep the car.
2015 M4 Mineral White/Sakhir Orange 6MT
Retired 2007 335i Montego Blue/Saddle Brown 6 MT
Retired 2006 325i Black/Black 6MT
, on Flickr[/IMG]