Average Broadband connection. Review on BSNL Broadband

Hi frnds. I am using BSNL broadband connection since two and half years. my plan was BB675 plan( 25 GB @ 4mbps and post unlimited @Mbps speed . In starting of new connection speed was good and there is no buffering in you tube @480p( high speed) . from the past 6 months speed was not good . I am getting only 2 Mbps speed instead of 4 Mbps sometimes on 0.5Mbps speed also which irritates me very much. continuity of the service was also average since if I got the service disconnected it may take days to rectify the complaint. coming to the billing part, now I am aishwaryasingh23ing 740 rs monthly, here service tax is itself nearly 100 extra. only good thing is that there is no extra charge for landline connection and can make free calls allover India from night 9 to morning 7 a.m . other ISP providers are offering more and exciting plans like 100 Mbps speed at the same cost . for eg; YOUBROADBAND is offering 100MBPs speed @ 800 rs