I have been using #mtnlbroadband since last one year and I never got any type of problem. Speed is consistently very good.Though its customer care is slightly traditional but its OK.I have tried almost all service providers i.e. Hathway, Tikona etc.
All are rubbish and later on their speed drops to few Kbps and most importantly they sent massive bill after 1-2 months which is highly unacceptable by me.Of course if anyone has lots of money to throw, they can opt private operators.