They are really nice and comfortable, at least, the shorts version is. (I don't completely love the chamois, but it's better than the other pair of Castelli shorts I own(ed), and it's better on the road bike it is on the CX bike.) If I remember correctly, they do pretty well in the heat too.
Funny thing is, I ended up with them by accident--I'd ordered a different Castelli short and a jersey, and a CS rep called me back and said "The jersey's out of stock and we've just discovered a manufacturing error with the shorts. Would the Body Paint shorts be OK?"
I think I still get a touch of sausage leg with them, but that might be because I haven't actually been riding much this year...