I’ve read the articles on these along with the tear downs and I like what I see. It does appear that the carb must be removed from the engine though to do any serious jet changes. And the metering rods are Demon specific meaning the Carter/Edelbrock rods will not interchange. But once the intial tuning is performed, then I expect the carb to be even more robust from a daily usage standpoint than their Carter/Edelbrock counterparts simply due to the jets actually sitting above the fuel reservoir floor rather than in it. The smaller than normal primaries should help both lowend response and fuel atomization at the lower rpms. The air demand secondaries should have the carb supplying no more air than what the engine actually wants assuming you don't get wild in the adjustments.
If all goes well, I’ll be receiving two of the carbs for a dual quad Y project I’m working on. The adjustable secondary air plates should make tuning much more easier than the weighted air plates that are found in the Carter/Edelbrock carbs.
Lorena, Texas (South of Waco)