Costs of Painting versus Grit blasting

We currently have some aluminum die castings that are painted silver after machining solely for appearance. We're thinking it might be a cost reduction to grit-blast instead of painting as the end result would look similar, and in use the paint wears off in a short time anyway.

Parts would need cleaning either way, and painting vs blasting is similar in that some piece of equipment is spraying the part, so the pre-treatment for painting is where the savings would come from. Is this reasonable thinking? Any fails or pitfalls we should be watchful for?

Thanks in advance...

Bob