The actual connection speed is actually quite decent. However, I have this issue (and from some googling it seems its quite a common problem) where the connection will occasionally cut out for seemingly no reason and I have to take the adapter out and plug it in again. It has its good days and its bad days; some days it might not cut out at all, whereas others it will do it every few minutes. I've tried numerous things to fix it with no avail and even after I formatted my computer it still did the same thing so I'm going to assume it is the hardware that is the problem rather than the software.
Overall, if you're lucky enough not to have this rather annoying error, it is actually quite a decent adapter.