I recently bought a house in Maine and all the sinks are fitted with drum traps. I have never come across these before and I don't see what advantages they have over what I am more used to, namely P-traps and S-traps. I can see that the drum would trap more debris before it could get into the DWV pipe, but once the drum fills, unless it is cleaned out, the debris will go into the DWV pipe anyway. So can anyone explain to me why I should keep these as I go through my house and update the plumbing. For one thing, they take up a lot of room in what is normally a cramped space.