If I do not feel strongly about it, then I will go with the group.
Now, there have been times when the players research some of the online power builds that many have said are technically correct but I say no because the cheese is strong.
I have a player who used to do this (I remember he even tried a CoDZilla build back in our 3e days). I'd always just let him.
But here's the thing, most of these builds are ivory tower builds that don't survive contact with a "real" campaign, they're just too focused or specific. Or they take way too long to get online.
The only time I've encountered truly munchkin/horrible builds was when we expressly did some high level one shots to stress test the system. But since I was expecting them and munchkined out the scenario/monsters it wasn't a problem (and was actually really fun to let loose!)