Sennaspirit, I've owned a dozen Hondas in the last 21 years, 5 of which I purchased brand new, so you're not going to hear me say anything bad about them. I never had the pleasure of owning a S2000, but from everything I've read, it is a fantastic car, but as PATPUR already mentioned, fairly common. Slalom and skid pad #s are nearly identical with the XF, but the Honda is about 1 sec. quicker in the 1/4 mile, if that sort of thing matters to you.
Bottom line, it should come down to which car looks the best to you, and which one you feel the most comfortable in. (one suggestion, take a good long drive in both of them, especially the Crossfire, because sometimes it can take a little while to find the perfect driving position) But unless you are 6' 5" tall, you should be able to find your "sweet spot". Since I've never driven an S2000 I can only comment on Accords and Civics, but to me, the XF "feels" like a more expensive car. (After all it's mostly Mercedes Benz, so why shouldn't it?)
Personally I think the XF is a far greater value for the money, because even though the S2000 and the XF have similar "window stickers", the XF can be had for 1000's less. For that reason, and its exclusivity, it makes the Crossfire a "slam dunk winner" in my book.
Good Luck!...Mike