Hmm, a friend of a friend has offered to sell me his RME Fireface UC for $600. Used, but looks to be in pristine shape. The guy selling it says it works perfectly, and he is totally vouched for by someone I trust. Worth considering? I know of RME's reputation, but I have never heard their products, and don't a lot about the UC.
Frankly, I normally am not a big fan of buying used electronic hardware...