Here's a test with Google's speed test, and this thing blows me away! In a
USB 2.0 port it gets 131.6 mbps download and 10.3 mbps upload! Thats very close in performance to the $20 adapter I use in my own PC! (This is while connected to my 5GHz bandwidth)
I do find that these tend to be unstable. On some PCs they get 60 mbps download, on others more or less.
Also, it's not pictured, but this thing is in fact dual band. I can connect to my 2.4GHz or 5GHz bandwidth.