Hameed,

You probably will never get any answer from Treynor for this 2 years old post. From an ex M3 owner and a current GS owner's point of view. I'd say GS and M5 are in totally different league on the handling section. The suspension design and weight distribution of GS are far short than M5. So even with coilovers/braces/wheels and tires, Lexus still got a long way to go before they can catch up with Bimmer.