When I buy my first phone I first thought which network should I choose my frnd suggest me tata docome and seriusly in the first years it always shows full signals and the data packs were quite good but in roaming it not always shows signal sticks and doesnt is very good to use.
Though tata docomo is a very big company but still it lacks in their network. although very good network gives a good 3g speed but lacks in roaming. Customer care service is quite impressive and are very helpful.