It actually does not matter as their customer service is pathetic. Does it matter if I have 100 Mbps connection from BSNL if it does not work for 70% of the time? I had a BSNL connection but got frustrated and switched to Airtel. They resolve my complaints, if any, within 2 hours and my work is not hampered.
An Airtel engineer told me that BSNL's systems, wire and boxes are 100 times better than Airtel's but they are not maintained so they keep breaking down. Airtel's system are continuously serviced so they don't keep breaking down that often (of course this is in my area and I cannot comment on other areas).
Now, I have a 40Mbps VDSL connection with 1 Mbps upload in the same price as my 8Mbps connection.