Staying with .43 is not an option with the many bug fixes, security issues and other improvements the newer versions offer, and offer continuously.
You may be setting up your network as a bot net for who knows who...
John's doing a good job so far at backporting security fixes (at least those that are documented or recognizable out of Asus's GPL releases). So long people use his fork rather than my own 376.43 releases, they should be relatively safe.