I've had good luck with mine. With the exception of adjustable secondaries, it doesn't seem to be much different than the old models. The adjustability aids in tuning out lean spots from early secondary opening. Something people used to drill holes to accomplish this on the old carbs.
I wouldn't bother with the electric choke. It's just a pain. I wish I hadn't got the electric choke model.
At first, I had a bad bog. I had to put stiffer springs, advance the initial timing, and put larger dia. accelerator squirters in to completely cure it. Since then, it's been great.
I don't know about those guys who have thier carbs run perfect out of the box. Carbs take tuning, end of story.
Otherwise, its just like the old edelbrock performers. Easy to tune, simple Carter based system.
What it boils down to is,... if you are familiar with and like the Carter carb, then the AVS is the way to go.
Volvord has created an extensive chart for Edelbrock tuning. It'll save you a pile in rods. The Edelbrock charts are kinda vague and designed to get you to buy more parts.
DON'T BUY THE 50$ TUNING KIT!!!!!
http://www.telusplanet.net/public/gilesij/Volvord/carb_jet.htm
Do, however, buy the 5 pack of air horn gaskets, they go silly after a few jet changes. Nothing more irritating than a vacuum leak.