You aren't going to win a much larger pot by slow-playing a set, you're only risking losing a big one.

Besides, there are ways of fast-playing monster hands which conceal the actual strength of your hand just as effectively as slow-playing. Don't think that just because you aren't passively check-calling that your opponent has any idea how strong you are. Doing things like leading into a preflop raiser after flopping a set or quads, or raising a preflop raiser the minimum on the flop actually convinces them you're weak a lot of the time, while serving to build the pot. This often allows you to win a huge one, much larger than if you had slow-played.