I have not seen much of Nishikori, but in his loss the other day to Ferrer, he hits some of the most impressive angles I've ever seen. It's a testament to Ferrer's tenacity that he hung in there against those type of strokes, he was really being dominated on every point but managed to pull it out.
I'd kill to have 1/3rd of Nishikori's backhand.
3.5 player. Equipment: Prince NXG OS, hybrid kevlar mains/poly crosses 50 lbs