Both players of similar caliber when at peak. Both have similar forehands although Roddick hits with more spin and Wawrinka's probably faster and less consistent. Who's forehand was better overall? Have a vote.
Djokovic. They all have the same fantastic grip. Pointer Knuckle in the bevel number 4.5, more commonly called extreme semi-western grip. Extremely good if you want some wrist pain after the match.