Due to the nature of the GS, I too would suggest the Michelin Pilot Exalto A/S or even the Pilot Sport A/S Plus (although expensive) over the Goodyear Triple Treds.
More info here... http://www.tirerack.com/tires/tires.jsp?ti...ot+Exalto+A%2FS
And here... http://www.tirerack.com/tires/tires.jsp?ti...port+A%2FS+Plus