thoughts on the edelbrock sp2p manifold

If you were having vacuum issues with the performer, don't blame the intake design. Maybe that exact intake is machined or something else is wrong, but not the intake design.
Also, just because the rating is to 5500 rpm doesn't make it a bad choice for your engine. It is capable to that rpm and if your not going that high in rpm doesn't make it a bad intake o a wrong one.
Baseing the intake on this is bad thinking.
The SP2P is exactly what you said is was, a gas crunch intake designed for more mileage.