doubleofive said:

Although I do think the comparison is a bit unfair. I mean, Spielberg has made a lot of movies that don't have visual effects at all or a minimal amount, while all we can compare them to on Lucas' side are the SEs and Prequels.

Argument rejected!

Look, fair or unfair does not have anything to do with it. This is a competition between two men. All that matters is which one is better, whatever the reason. For example, is it fair that Spielberg was born with a natural ability to act? Is it fair that Lucas was blessed with a better beard (barely)? And yet, these are indisputable truths.

Further, you can argue that Spielberg's decision NOT to use CGI, or make movies that barely require it, means that he is making better use of the technology. Maybe if Lucas wasn't so Lazy between 1983 and 1999 he could have made some movies that didn't need so much CGI.

In summation, Spielberg takes the lead. Who else has an opinion?