The zinc works to prevent rust because it corrodes instead of the steel.

Painting the SURFACE of the rotors with a black paint actually gives a nice, clean look to the rotors. When braking it takes the paint off leaving the nice surface underneath.

POWER SLOT ROTORS

Im not yelling but strongly emphasising that. I love my powerslots. ive had 3 sets now and absolutly no problems.

Do they rust?

John, Powerslot rotors are plated. The vents don't rust. I can shoot a pic if you like.

Yes please. My wheels are pretty open. I hate the rust.

you're not going to paint the braking surface are you?

Even if you did, it would be gone in minutes. We're talking about plated rotors. The pads break through it very quickly, leaving the normally rusting surfaces (the edges and vents) plated and rust-free.

exactly what wilwren said no rust due to being lated the have never warped on me either so those are your best for you $$$$$

http://www.powerslot.com/pages/powerslot_info.html This page explains the problems
with crossdrilling and shows an example of a failure for those that are interested. Powerslot uses Brembo blanks (thicker than OEM) and slots them to the minimum rotor thickness, then plates them. Brembo blanks are among the best in the world.

Mine after nearly a year (shot this morning):

Like Bill said, it would be gone anyway after braking. But as I said, it gives them a nice clean look afterwards (probably doesn't last that long, but it'* good for car shows/ presentation).