We have a Diaper Champ for the exact reason you mention: that it uses any bags we happen to have around. Since we live in a house with a yard and twice-weekly trash pickup, getting rid of stink is a small matter; in fact, I don't think we've ever said, "Wow, the diaper pail smells! We need to empty that right away!" If we had a studio apartment with no dumpster and weekly pickup, I can see that we'd prioritize odor containment.