Acrylic Enamel vs Acrylic Urethane

I've sprayed a solid color single stage one other time. It was on JohnnyDart's 65 vert engine bay. It seemed to go down pretty well and still looks pretty good. I dont recall what it was exactly.

The flake/poly in the mopar colors are not that big. Im looking for whatever lays down the best and I might be able to cut and buff. But then again its only the engine bay.

How soft are the enamels? Ill be installing the engine very shortly after painting.

If you are dead set on cutting and buffing, your best option is a base/clear urethane. Cutting and buffing single stage metallics means you will be cutting some of the metallic itself. I would not cut and buff everything, just spot sand any trash and buff that area leaving the rest alone.