Well, I had the mechanic take them off and coat them before he put the new motor and trans in a couple weeks ago (I still have to fix a leaky radiator and tranny line).
He put three coats on, and after each coat he put them in the oven at 600* for 30 minutes.
How much is this going to help the car? Will it be noticably cooler or really help the exhaust flow?
I'll try to take pix this weekend when I go and do some cleanup on the car. The car is starting to look good, but needs a carpet shampoo, and wash/wax before it really shines.

Won't help much with engine temps, as most of the heat comes from within to begin with, but it will possibly decrease the engine bay temps.

The big advantage is holding the heat in the exhaust to keep it flowing better. Get it outta there quicker and easier.

You will notice a difference in the underhood temperatures. Both my n/a set of manifolds and turbo ones are ceramic coated with no heat shields used on either set except under the cables that connect to the throttle. Horsepower increase is harder to judge.

I wasn't expecting as much of a power gain (so miniscule it wouldn't be noticed I figure) as a temp drop under the hood.

the PEMs, Pector55 did for my Regal have a 2000* ceramic colored powder coat......they hold in heat REEEEL well, but I still wanna get a crossover pipe heatshield.....BTW if anyone is condidering PEMs Hulkspeed.com is the way to go....he took a little while to do mine, but they came out looking like a piece of candy, and he has very good customer service as well (my PEMs took about a week longer than expected to make because he was having trouble with his powder coating so he upgraded me to the ceramic 2000* finish for free ::a $50 value: I believe Sol has his PEMs too