Forgive me if I have missed a vital piece of information- I have done my best to read through these and other forums in an attempt to finalize my decision on an ALFA Wireless adapter. If my summations are incorrect then please feel free to post a recommendation or correction.
Lenovo Thinkpad R61 Running Backtrack 5 release 2 GNOME64.
AWUS036H - The tried and true adpater due to its chipset (and the clear front runner around the security community), but its main limitation being that it is not 5 GHz (802.11n) compatible. Excellent energy for survey and injection, otherwise. Solid drivers. ~$30.
AWUS036NH - The first iteration of the aforementioned adapter, has experienced issues with BT4r1, BT4r2, BT5 and BT5r1. From the brief posts that I've found... it seems this, as well as others, have had most of their issues with monitoring and injection ironed out. Some recompilation of drivers may be necessary. ~$35.
AWUS051NH - A decent card and similar to the AWUS036NH, but the underlying difference of transmit power puts this card behind. Also some issues with injection ... perhaps stemming from power/range issues. Similar driver issues. Unsure if BT5r2 has OotB compatibility.
AWUS036NEH - Smaller footprint and capable of N. Unsure of the actual performance, but it appears to be the solid choice. I may prefer the latter because I'm bad about breaking dongle style adapters off. Attractive as one of the cheapest at ~$21.
AWUS036NHR - The newest release (I believe) in the AWUS036 line. Solid power but plagued by much of the same issues for drivers and monitoring/injection. I did find a decent post about how to overcome this. Also one of the priciest at ~$50.
Additionally, most of the issues that arise with driver issues were compounded by users running Backtrack from a KVM, VMWare or VBox installation. To alleviate this, I will be running my installation on the local HDD. My use of these tools will be white hatting and educational (labs, etc.). I also understand that 802.11b/g/n adapters are a little weak on the 2.4GHz power range, but I can accept this as I will be (eventually) investing in a good Yagi.
I'm currently leaning towards the following:
Option 1 (if feasible) 1xAWUS036NH. This would provide decent power for most of the situations I would find myself in, provided I can get solid driver performance out of BT5r2. Versatility at a good price point.
Option 2 (if necessary) 1xAWUS036H and 1xAWUS036NEH. The tried and true method with an option to get into the 5 GHz band. The most "reliable" for survey, but at the cost of power requirements and USB ports.
Option 3 1xAWUS036NHR. Similar in price to Option 2, but still carries the risks and drawbacks of Option 1. Definitely last in priority.
Once again, I apologize if I missed anything obvious. I'm very new to ALFA adapters.