I am using Tata Docomo sim from last few months and I am very disappointed with the signal strength whenever I sit in my Basement or First floor.I Can’t be able to speak on my tata docomo sim due to poor network connection and On the other hand They also doesnot gave any offers.Very less service centers are available.When I call on Customer service I am not able to speak with them.Call rate and Internet rate prices are also very high as compared to other operators.