After all, I have no way of knowing what they're up to. It may be good or it may be bad; I can't know. (I suppose I can set up a router to discard packets with the RFC 3514 evil bit set, as a show of good faith, but...)

So I think the risk should be low, but that's just, like, my opinion, man. My opinion doesn't mean that the risk is in fact low.

Has the risk of running an exit node ever been tested in court? Many people, myself included, simply can't afford to have that kind of experience even if we're reasonably sure that it will end up OK.