I had been using bsnl broadband for over a year now. I can say that the service is good till the time it is running.But when a problem comes up then you may or may not have to run from pillar to post. As in other government services bsnl service is not reliable as to when they will rectify the issue.
Once I received prompt service and once had to follow up for about a week to get the net restored. Quality of broadband depends and is not constant and that UPTO mentioned in their plan in most important word to note.
This UPTO level reaches during no peak hours. If you are using bsnl for official work then need to be careful about their non constant quality. So if you are planning to go for bsnl then be prepared for not so friendly customer care.