Honestly that DNS Redirector doesn't look like a cooperate solution. I'd rather use DNS filtering as presumably it would use less resources on my VM servers than something like a proxy server would, which can use a fare amount of resources to keep up with demand, DNS servers on the other hand are a lot more lightweight.

I'm not paying for a web filter solution I will preferably use NxFilter or make my own Squid box. Why would I go for a paid solution just to get auto-updates? It's super easy to setup WGET on windows with a script to download files, move the correct file to the needed location and then cleanup when down, and it could even be run by the task scheduler. We're still using DNS Redirector today - auto-updates categories, and doesn't require Java - not much AD integration beyond password bypass, but that's all we need.

I tried it - did not like that it didn't auto-update the blacklist categories, and technically the sources of which are for non-commercial use - did not like that it required Java on the server.

Nxfilter how to not cache a page