blue is the bomb. the rep i talked to said the RC4 and RC5AL are their two best handling frames, but that the RC5AL is actually the lighter of the two(if that sort of thing matters to you).
the geometry of these bikes is definitely aimed at racing, though, so if you're looking for something that will give you a more upright/relaxed riding position, it's probably not the best choice unless you like lots of steering spacers.