If it ain't broke, don't fix it IN.
As for the Mavics, they make sense to someone who want's bombproof wheels that are light and that have a high weight limit. Are they worth the cost? I used to think I'd never be able to justify paying that much for a set of aluminum clinchers, but I think differently today.
FTR, I have a set of '11 Mavic Ksyrium Elites w/Conti GP4Ks. I see no reason for going with anything else other than bling. I don't ride in a way that I'd benefit from the aero benefits of deep carbon wheels (although I love the aesthetics).
I can't have a custom set built better than what I'm riding now for what I paid for them ($600./incl. tax, install, everything).
IMO, the best way to know for sure is to test ride a set of the Mavs you are considering under the conditions that you ride regularly and see if you notice a difference. I suspect that you'll notice a huge difference in stiffness and performance. But then again, it's not fair to compare a $500. wheelset to a $1,000.+ wheelset.