My vote goes to Roddick. For all his vaunted power, it has trouble deciding between a deep, flat shot like Blake's or a heavy topsin like Nadal. So, it finds itself in the middle w/o the advantage of either.
For the pure look of it, he lets the ball get too close and so has to windshield wipe it for it to go over (and thus the lack of depth and power.)
Incidentally, it's a washout now at the USO so I'm forced to watch Sharapova's equally ugly reverse over-the-same-shoulder forehand where she, too, lets the ball get too close so has to finish it over her head/shoulder. And her forehand comes with grunting
They're a great couple after all