i have a 2007 g35x so hopefully i can still give you some good feedback. the G is definetly lighter, feels alittle quicker, turns better and more reliable. the 540i has better low end torque, better seats, cabin noise is much less, and overall better engineered(then again MSRP of the 540i is double the G so its a given).
as DinnanBimmer said, if you were comparing an i30 to a 5er, its laughable comparison as the i30 is light years inferior to the 5er.
Last edited by mifesto; 04-09-2012 at 02:47 PM.