I bought this: TP-LINK 150 Mbps TL-WN721N Wireless N (Link)
It worked good for two months. After which it stopped working. I haven't got time to send it to Mumbai and so I just bought a Card based adapter. (I will sent it for RMA later, when I get time).
I bought this later: D-Link DWA-525 Wireless N 150 Desktop Adapter Network Nic (Link)
It's been one month for the D-Link card. And I don't have to worry about USB getting unrecognized again.