I started using Theme File Duplicator on WordPress 3.2.1 and didn't seem to have any issues with it... until recently.
I'm currently using Theme File Duplicator with WordPress 3.5 and it works, ok. However it has a really annoying quirk. Theme File Duplicator does not identify any of the custom page templates which are part of the theme. So, when it is time to duplicate a custom page template, I have to start by duplicating some other file, then copy/paste the information out of the original page template I wanted to use.