It usually disconnected after a few minutes of heavy use, such as torrenting, streaming a movie from Hulu, or uploading a heavy amount of data to my server; sometimes it would disconnect randomly.
It was cheap; and "just worked" when I plugged it into my Ubuntu laptop
At random times, the card would disconnect and not re-associate with the AP; To get back on the wireless network, I'd have to unplug the adapter, and then plug it back in.