I'd want to show that big of a purchase off! And yes, the red reminds me of the Porsche caliper too!
I'd say if you want to show it off, not that it won't attract attention anyway, go for the red. But Pete has a good point on the color scheme thing. With the black car, you are safe going either way.
Got pictures of either? Just to better imagine the look?
I think if it were my decision, even on silver, I'd do red.

But look at me, you know I like flashy, my calipers are blue!
