We purchased an Alfa 2 years ago along with an 8 DB gain antenna through Ebay from 2 different vendors. It works fine. Reading all the information on the RadioLabs USB antenna I decided to also purchase that one a year later so that both of us could get online at the same time. It also works fine. Interesting that there are times when the Alpha works better than the Radiolabs and other times vise/versa.

With the Alpha we've been able to get good wifi at anchorage at a distance where I could hardly see the hotel it was coming from. Probably about 3/4 mile.

I've had good luck with both.