I used the G2 paint kit to do my calipers on the cobra.
It is an epoxy based paint and very tough. It would be much better than regular paint but not as tough as powdercoating. Powdercoat is cooked at 400 degrees for about 30 minutes so you cant have any rubber seals left in there.
I plan to paint the ones on the focus when ever I redo the brakes.
Oh, If you paint the rotors it will make a huge difference also. I painted mine while still on the car. Just use painters tape to mask the pad surfaces and bolts. remove the calipers. Dont forget to also get the outside of the rotor and fins. Mine were like this for about 3 years and still looked pretty good when I replace them last year with new rotors.
2003 SVT Focus, Comp. Orange, EAP. Cervini's rear spoiler, Eibach sway bars, Steeda Springs, K&N filter, steeda shifter, VF dog bone, Massive camber arms and toe links.
other car: 2004 SVT Cobra Coupe, Screaming Yellow, 2.76/2lb lower...