That makes it hard to determine "which one is better". My gut feeling is that Chrome is better at protecting your computer, while NoScript is better at protecting the data you enter in the different sites. Since one can't reasonably expect every site out there to have decent XSS protection and to be kept up-to-date with the most recent attack vectors discovered, by minimizing the amount of untrusted code that runs in the same page context (something that Chrome's sandboxing can't do anything about) the chances of private data being leaked from one domain to another is decreased as well.
There are plans to port NoScript to Chrome, which I believe would be ideal, but unfortunatly it's been held back by the lack of support to synchronous access to the page assets by individual extensions. That means one can't inspect a script before it's already executed, making many of NoScript's features unfeasible (and also meaning alternatives such as NotScripts will never achieve a similar level of security).