I got the MTNL Triband broadband connection about 6 months back and am happy with it. There were some teething issues with it, which were resolved through the MTNL service helpline number 1504.
Have opted for the Rs 200/- (subscription) + Rs80/- (router rent) per month package and am billed every month with my land line connection.
The browsing and download speed is very good. Am able to download at close to 26.5 kbps regularly.
However, when the connection is on, the audio on a normal phone call is not very clear. There is a perceptible background noise similar to the noise of a dial up modem establishing connection, which can be irritating. At times, I have had to switch off the router and break the broadband connenction to converse clearly on the phone. But since I have a cell phone connection this is not really an issue, as I dont really miss making calls on the landline. Also, my usage of the broadband is not more than an hour everyday, so I can live with this problem.