Since I couldnt decide whether grass or hard courts he is greater on considering his whole career at this point. He was a great grass courter from 2006-2011 and has been a great hard courter from 2008-today. 2 Wimbledons and 2 U.S Opens, only 1 Australian, but tons of Masters titles on hard courts, many Wimbledon finals. I dont really know which he is better on overall at this point and thus which is his middle surface and which is his worst one.