I wouldn't say he's overrated. He looks threatening when bowling and more often than not keeps it tight. He can swing the ball both ways, which few people in world cricket can do nowadays. He's definitely the top quickie for India, though RP has also been performing very consistently recently.
He can only really swing it in England or New Zealand. I have not seen him swing it much other than in those two places. He keeps it tight, on his day, but with an economy rate of 3.29, this is obviously not often the case.