I am using docomo sim right now, and it has a good network coverage in my area. the calling rates are very low and offered with low rates.
Docomo offered many special STV, net packs, SMS packs with reasonable rates. The customer service and their support to resolve the problems is very nice.
The main drawback of this network is its coverage area. in some areas there is no signal and unable to call. It has best roaming offers and net packs.
The call droping problem is very less in this network. it is best reputative brad in India.
The activation process of this sim card is very fast when compared to other mobile networks in India.
So I strongly recomended this for others to gain best network, best calling rates and net packs.