Which lens: 18-135 or 18-200?

For the same price, I have the opportunity to buy a 60D with one lens. The 18-135 or the 18-200,mm, both from Canon.

Which lens gives the nicest results, considering sharpness, distortion, CA, etc. I can't make up my mind, both seems to have their weakness but both seem OK for a walkaround lens.

Thank you.

--
Jean-Pierre