The data produced between Google Analytics and AWStats is inevitably different, mostly because of the different tracking methods they employ. AWStats is designed for network administrators and engineers, whilst Google Analytics is made for business owners, marketers and analysts.
Which tool is best?
Both tools are useful for different things. If you are wanting to monitor network and bandwidth usage, AWStats is the better tool to use. If you're looking for statisics from a visitors/business point of view, Google Analytics provides you with better information regarding demographics, visitor behavior and traffic sources. A lot of the stats that AWStats provides are purely meant to inform you about website functionality and finding out more about the technologies used by the site’s visitors. Google Analytics is a platform that allows you to discover the why’s (or usually why not’s) and how’s of the interaction of website visitors with your site.