I voted Holley because you already have it..........in case someone here points out that the guy that hates holley recommended one.
The small port heads like single plane intakes, going to the dual plane will be going backwards, IMO.
I have had streetmasters, while not as good as a street dominator, (IMO) they are better than the Performer.
The performer manifolds always left something to be desired, I like the cast iron manifold better for performance.