I put General GMax AS-03s 255/35 ZR20s on my '13 GS as my winter tires. They're definitely a lot louder than the Pirelli's that came with my car, but they are a decent tire for the price.
http://www.tirerack.com/tires/tires...ll=Blackwall&partnum=535WR0GMAS03XL&tab=Sizes
http://www.tirerack.com/tires/tires...ll=Blackwall&partnum=535WR0GMAS03XL&tab=Sizes