Thanks for posting your question here! Increase in sales of the Plugable UGA-2K-A caused it to go out of stock. Sorry about that!
A consignment with thousands of units are in transit and should reach Amazon by the end of the next week. It would be available for sale around Oct-17-2011.If you want us to notify you when the Plugable UGA-2K-A comes back in stock, just shoot us an email at email@example.com and let us know. We will be glad to notify you.
You are absolutely right about the only difference between the Plugable UGA-2K-A and the Plugable UGA-165 being the resolutions that they support.
The Plugable UGA-2K-A supports resolutions up to 2048x1152 when connecting through DVI while the Plugable UGA-165 supports resolutions up to 1920x1080 through both DVI and VGA.
So if your monitor has a native resolution of 1920x1080 or less, the performance would be the same if you used the Plugable UGA-2K-A or the Plugable UGA-165.
Hope the above information helps! If you need additional information, feel free to post back here or shoot us an email at firstname.lastname@example.org. We are here to help!