I have been using the product for 8 months now. You need to understand that nothing comes free. You won’t get portability, high speed of 3 MBPS etc. for 1000/- per month.
Speed
The sales guy told me that on average I will get 300-600 kbps during day time. And at night it will be very high, at least 1 MBPS. I have never exceeded 600 kbps at night. During day time I get less than 300 kbps.
So don’t expect very high speeds of "up to 3.1 MBPS", it’s just marketing gimmick.
Cost
It is expensive than land line based broadband but you get mobility. You pay for the modem, then monthly subscription which is way too high than Airtel or BSNL. In Tamil Nadu, there are only 2 cities where high speed connection is available. So check where you travel before buying.
Connectivity
It’s okay. Gets connected 99.99% of the time. Sometimes it goes into CDMA mode and connection is 128kbps (Yuck!!!). But it connects. I live in Perungudi in Chennai. In Nov the connectivity was very bad but now it is okay.
I am disappointed that it is just normal speed connection (300kbps) and not high speed (e.g.1 MBPS) 300 kbps is as good a dial-up these days. But I use it to download games, etc. and does it good. So I am living with it.