Frederick-
Have you seen this June 2013 article on a "code execution vulnerability" in w3tc?
Also, I have a loaded question on the latest version of w3tc - I've been holding off on upgrading beyond version 9.5.2 because it works with no problems, and I've been monitoring the support forum since the big 9.2.6 upgrade and it appears that each subsequent upgrade contains tons of new fixes followed by hundreds of new support posts. The most common ones now seem to be related to the master.php file and blank pages. I really want to upgrade because I see many security fixes in the latest versions. What's your take on the latest version and the issues being experienced by the support forum users?