After I pulled together the review that is summarized above Slash of AR15.com forums got busy and worked up a replacement buffer for the AR-10. What is unique about Slash's solution is that he made his buffers 3/4 of an inch shorter so that with the use of his buffer you could use a standard AR-15 CAR stock, buffer tube, and AR-10 A2 spring to convert your AR-10 to a CAR-10.
Following is a photo of Slash's Buffers:
http://photos.ar15.com/ImageGallery/...ImageUnq=30943
Here is a thread where Slash describes these buffers...
http://ar15.com/forums/topic.html?b=...0&t=229073
Note, I am using the factory Armalite stock but Slash's solution looks like a good solution as well!