If your other carb was sputtering it almost sounds like it has issues and is in need of a re-build? Either the accelorator pump was bad or the float?

Newer carbs have plastic floats in them and need replaced a lot more then the old brass floats. Unless the brass floats sprung a leak.

Since you mention you used the same distributor again after you swapped out the carb I doubt the vaccum advance was causing the engine problems.