Contributing to the discussion, I would say that Reliance & Tata datacards are the Best choice for us till date. Both of them have Excellent Speed >600 kbps which is good enough.
I am using Reliance Net Connect Broadband+ for Video Downloads & Video Chats as well. I feel its very fast while browsing also. I am using Broadband+ 5GB plan Now planning to shift to 3 GB plan as they have reduced their tariff rates on additional usage to .50paisa/mb. It is good for me as Everyday 18 hours I need to remain online, basic requirement for Import Automotive industry. In Vijaywada.No network problem.
I have heard from my friends that Tata is also good for speed but perhaps servies are not launched in my city & many other cities.Except Coverage.I did not find any problem with TATA.
Anyways.presently I am enjoying with this.Only thing they need to Come up with Vigilant Customer Support to avoid delays.