This one at a town rest stop is pretty good in that it's fully plumbed, more often than not they're long drop or dry (composting). Sometimes though it's the "wet" ones that smell and look the worst. This one encased in a low unlit concrete shell smelt of shit before I ever sat on it. I know better than to inspect the bowl now although an under seat bug check has become routine. It's cool in here, almost cold and the soothing wash of the next door urinal literally seeps in under the door.