BSNL Broadband + Vodafone 3G ?

I want to change my current Home 500C plus to something else. I need 4mbps speeds but do not want to spend more than Rs 1200 month. I am planning to have BSNL ULD 900 (annual pay, costing me Rs 750 per month) and activating Vodafone 3G. I need to have internet on my phone always, official purposes. But BSNL ULD 900 speeds reduces after 8GB. When that happens I want to use my Vodafone 3G for downloads. I stay in Mangalore, Karnataka and I get 3803kbps with Vodafone 3G. My total bandwidth consumption is around 6GB-15GB. I was looking for a way to use both home internet and 3G for my internet usage. Is there any better combination ? Recharges seems expensive for 3G. Which one is better ? Also, I am a little hesitant about this plan because Vodafone provides 3G in Mangalore using Airtel and Govt. is trying to ban 3G sharing.

(1)Try FireFox browser with addons Adblock Plus/ NoScript/flash Blocketc. You can block and see pictures/video/advts etc as you like from the same websites/or any site. visited often. this will make your 8GB quota increase at least by 30% to 40%In case some web sites do not respond properly ( specially Indian web sites ) add on IETAB, will make FFwork as IE (2) If you are checking usage in BSNL web sites often, avoid and check locally withNetworX or Shaplus. ( say check accuracy with BSNL in one week )

I already do all these things. Yet my consumption is 6GB - 15GB. That is for sure. I now need a plan which suits that.

Get the 1000 uld plan, if 15gb is enough for you and use 3G only when no other option is available.

Comparitively Vodafone is more expensive. Airtel has Rs 1250 for 10GB plan here. Also, like I said Vodafone is currently sharing 3G with Airtel here. Depending on the verdict (Govt. banning 3G sharing), Vodafone might lose 3G customers here. Anyways, 1000 ULD you mentioned is 2mbps. I am looking for 4mbps+. BSNL 900 ULD gives that till 8GB. If there was recharge for Rs 200-300 with 2-2.5GB limit, it would be great.