I Agree Dom, but for guys that are class/rule limited to a 4150 flange baseplate carb- the twin blades are really the only option to get above 1000ish cfm.
Thats why im gonna get a 4500 for the Duster and leave the twin on the 65 satellite.
I would love to see what you could do with one of the 1400 twin blades now that the new company is making the parts and they are people you " know" rather than what we ,,, well, you know.
Some guys need the flow but, are just rules constrained.

Just thought i would send folks your way.