With or without taxes? And how many free calls?
Airtel 256Kbps UL plan comes for Rs.650+Taxes and has 100 free calls.
If this is without taxes and has free calls, then this practically is same price as Airtel's.
The advantage of MTNL is that sometimes speeds can go up to an uber cool 1 Mbps, pretty good but contary wise they sometimes fail to match even the promised 256Kbps.