well there seem to be one answer for every driver available It's kind of a trial and error work to find the best drives for your specific setup. The 23.12's work really well for me, as well as the 23.11's and the 21.83's.......not much of a difference speedwise.
Again, other people might have other experiences, so good luck in your search
i think nvidia leaves the 23.11's on their site cause they are the best yet. i used like 5 of the beta's, and I still get the best performance with the 23.11's. but its definetely setup specific