I would agree that the classiest and the best player I have seen is Federer. Personally, I hate the grunting as I see it as a deliberate attempt to put off the opponent.
However, Nadal has great technique. The ability to put the amount of spin on the ball that he does is almost unbelievable. The fact that Nadal has been able to adapt his clay court game to the other surfaces has to be acknowledged. Also, Nadal is not playing with his dominant hand: he is naturally right-handed.