If you are reading this, be sure you are aware of the slight difference in the model of  the Alfa AWUS036NH as compared to the AWUS036H.

The NH version is the cousin to the famous Alfa AWUS036H. Although on paper the NH's 2000mW Transmitter Output Power seems impressive and should be able to outperform the original H - it's actually quite the opposite in my opinion.  Also, many people have said that this adapter is not as great as it seems and had a lot of compatibility issues.
It is an updated version of the original Alfa AWUS036H and although professional tests have shown the NH version to have phenomenal range, typical users (such as you and I) have said that there were too many problems.  Click Here to See More information on Amazon.

ALFA AWUS036NH

I personally do not recommend the NH as since a friend of mine purchased it thinking he could "beat" me in the wireless range test.  It didn't work out too well for him I should say. It's one of the reason why I state in my review here that the H will be able to stand the technological test of time.

It is still a great adapter, but don't let the 2000mW be the only thing blinding you to buy this.  My friend wishes he could return it and get the 1000mW AWUS036H version, but maybe in due time Alfa will release better drivers for this adapter since as of current there is a lot of compability issues with this NH model because most wireless routers are set up for wireles B/G anyways.  N routers are virtually unused except by those who MUST have the latest and greatest. 

It is still a great adapter nonetheless, I don't want to say its the worst thing ever or anything.  If you must have it, Click Here to see more reviews on Amazon and if it fits your criteria first.