I thought I heard that the drivers are working in the Backtrack 5.

30 seconds on google turned up this post. Looks like you'll have to do some work, but learning what's under the surface makes you a better pentester.

http://www.backtrack-linux.org/forums/showthread.php?t=45323

i was looking at the specification of this new adapter, but i can not seem to find any good reason to get this one over the AWUS036NH, or am i missing something?

I recently bought an alfa R36 which can be used as an extender/repeater with the AWUS036NH, which also works great!

just some experience i want to share what i have had with alfa network:
at the time of purchase the R36 did not have compatibility with the AWUS036NH. i emailed them if they had any idea if this would be supported and if they had an ETA on the drivers that would support the AWUS036NH adapter. i received an answer within 24h (even with an apology for the delay because of the chinese newyear, now i dont know if my standards are low, but a reply within 24h is fast in my opinion) that the drivers would be released within the next few months. after a few weeks the updated driver was released and announced on their website. For me there is no substitute for alfa, i just love their products and the quality is excellent.

jup, it has been running non stop now for a couple of days, finally internet upstairs, these walls here are made of solid steel or something :S

i would go with the AWUS036NHA it has a atheros card that works better with linux and can go into MASTER mode for AP attacks much easier something alot of other alfa and cards in general can't do in linux