Re: Ah, capitalism at its best
"I'll specifically set cm or opera to use duckduckgo - go to use the browser shortly thereafter and the search settings have gone back to Google"
Are these shared devices and people just prefer other options?
I've never seen this happen on phones (and generally have the opposite issue when assisting people, struggling to reset settings back to defaults after someone tried something new) and have only seen it on Windows when profiles are corrupt/not saving so that the default settings are applied at each logon.