I have been using docomo for almost form 6 months from my college days. The network of tata docomo is miserable will get frustrated by using it. one can seldom make calls to any other network it take 20 to 30 times in peak hours to call any network.
Signal quality is at the worst voice clarity is pathetic and other features like caller tune, gprs is also woeful. these problem are common among all other tata docomo customers. I have verified from several of my friends.