Untangle vs squidguard or untangle + squidguard

I am running Untangle lite (older version from a year or so ago) and its doing most of what I want it to do.

I would like to set up squid to use as a cache for my clients, and am contemplating squidguard as I'd like to redirect certain URLs ("google.com" redirects to startpage.com etc).

I have read a few posts and such about installing squid/squidguard on an existing untangle system.

I am also contemplating a separate system for squid/guard, so keep my untangle install as "pristine" as possible. Plus I have an older system that draws less than 20w at the plug that is sitting idle.

Any comments or advice?