Both carburetors have their good and bad points. It really depends on what you combination is. If you have a pretty radical camshaft(low vacuum) either one will need a little tweaking to get things right.
I like Holley type carburetors on my racecars,and have been working with the Edelbrocks a lot lately,to me they are less friendly for serious racers. I am using an 800 Edelbrock on my current truck big block build,and am doing a lot of work with it on the dyno to get the cruise mixture and power mixture just right. Out of the box they are pretty rich to keep guys from melting down anything.
Keith