600cfm or 750cfm? That is the question??

Man, this is crazy! it's just all over the place. So much for a easy answer! :)
Basically stay away from the 750 Edelbrock and everything will be fine.
I'd get a Quick Fuel if it were cheaper. That street avenger 670 cfm does sound like an option...
How many Hollys are there???? There are quite a few to choose from. Which one is the good one? Avenger?