I got the tata docomo pre-paid card on 10th July. First about the call charges
local - 1p or 1 sec
std - 2p for 1 sec (it is currently 1p for 1 sec as promotional offer)
Sms - 60p local and 120p std (100 sms free after 1st sms)
The coverage is very good in Bangalore. I have not faced any issues with the network coverage. Call quality is much better than airtel itself. I did not had a single dropped call in last 13 days but the same is not true for airtel. Airtel customer care just tells call drops are due to congestion without refunding your talktime.
The worst part is none of the customer care number works. Otherwise this is the best and value for money service in Bangalore. My phone service took one day to activated and I had to go again to the dealer for the same. If you want to buy a phone connection then tata docomo is the way to go.
Once number portability comes I would be the first one to switch my airtel number to tata docomo if the service continues to be good. I will update the review if there are any changes to tariff or service quality.
Cheers,
Rishabh