F520 ("medium") Roughly similar in performance to the old F540, but inheriting the blue bezel of the F330, which was the previous "medium" server.
Actually, the F520s blue is a different shade than the F330s, but it is not a very noticeable difference unless they are side-by-side.
Here's some trivia: The Forest Green bezel on the F230 appears to be painted on over blue plastic. (At least the one I've examined. Are the 220/330 colors painted?
Prototype bezels are, I believe... the F220 we have has a very rough "painted" surface. I don't think this is intended for the final product. But I don't knwo for sure; I haven't seen a released F230 bezel yet. :)
Bruce