Overview
Carbon ceramic brakes are found available on the highest-performing sports cars from GM (Corvette ZR1), Porsche, Ferrari, Lamborgini and others. They significantly reduce unsprung weight and brake fade. However they are very expensive and fragile. Allegedly many tracked Porsches and Ferrari's swap their carbon ceramic brakes for steel ones due to cost. The general consensus appears to be that they offer little practical advantage for street use and that SL-C owners that track their cars would be better off spending their money elsewhere (i.e., driving coach). However, if you're doing serious racing or have deep pockets and seriously covet the bling these brakes bring, they are a great option.
The advantages to these brakes are:
No fading Carbon Ceramic brakes are extremely fade resistant
Wet effectiveness Unlike traditional brakes which can have initial wet-weather fade until the water is burnished off, CC brakes are effective immediately on application. Interestingly, some production cars with traditional brakes actually use the ABS module to pulse the brakes occasionally to rid the rotors of water so the first application will be immediately effective- such an approach is not needed for CC brakes.
No thermal deflection One contributor to fade is thermal deflection- the rotors actually change shape under extreme heat inputs. CC brakes trend to be impervious to this effect, and so braking feel is improved, and fade is eliminated or dramatically reduced.
Consistent pedal travel Because the rotors don't flex, pedal travel stays more consistent compared to traditional brakes
No Corrosion Unlike iron rotors, CC brakes don't corrode in normal use, thus keeping their effectiveness and beauty the same over time.
Increased rotor life For most cars, the rotors are lifetime pieces. This offsets, in some small way, part of the initial cost of replacing several sets of rotors over time, especially when labor costs are included.
No thermal cracking Iron rotors are subject to cracking, especially if drilled. CC rotors tend to be very resistant to cracking, so allowing longer life and better performance (cracking rotors are less efficient, as well as unsafe when they explode under load)
Mass reduction One key advantage to CC brakes is their extreme mass reduction compared to traditional brakes. This is something that makes for better acceleration, better braking, and better handling.
The key disadvantage is cost.
Superlite Option
The Superlite carbon ceramic brakes are sourced from the popular Corvette ZR1, which means there will be a long-term supply of rotors and pads, as well as significant aftermarket support. To add them to your SL-C, you'll need specific uprights (in stock now at Superlite), wheels of at least 20" in diameter (call the factory for details on wheel fitment), and of course, the actual brakes from either GM or a wrecked ZR1. Parts prices for the GM parts are below- call Superlite for the latest prices for the SL-C-specific parts you'll need from them.
Don't buy wheels until you talk to the factory to be sure you get the correct offset, in addition to the minimum wheel diameter to be sure of clearance. As most everyone knows, all wheels in a given size aren't the same. That's why you have to check-- just because you heard you can make a 19" wheel fit, doesn't mean that many (or any) 19" wheels actually do fit on the car and clear these brakes. The calipers and rotors are massive, and supposedly the same ones on the Bugatti Veyron!
Parts Prices
The complete set of GM parts needed (4 rotors, 4 calipers, pads, pins, etc) costs about $16K at retail prices. However, these numbers can be greatly reduced. For example, a poster on CorvetteFocums named RichieRichZ06 works at Abel Chevrolet and offers the complete setup for $8200, as of 4/2015. If you have a relationship with a GM dealer, you may be able to get similar pricing. This vendor (ask for Richie?) knows exactly what parts are needed.
There doesn't seem to be much of a used market for these brakes, but if you do find a set, please be very careful to inspect the rotors for any signs of chipping or other wear. Any such damage renders the rotor unusable, according to GM and their supplier. The rotors can be weighed to be sure they still meet minimum specs- look for the min weight stamped into the rotors.
Maintenance
The carbon brakes -- or the rotors, at least-- from a ZR1 will probably last the life of your SL-C (since you probably won't be doing 100K miles on it, the nominal life of the rotors, according to GM). But you have to be ultra careful when working on and around the car so as not to damage the rotors.
For example, if you are changing wheels, it's a good idea to lift the car just high enough so that the wheel can be slid off the hub horizontally, without needing to be lifted down or up. This approach minimizes the risk that the wheel could chip a rotor edge.
When working on the car with the wheels off, GM requires their mechanics to place a special cover over the rotors to protect them from errant parts or tools.
Can you get the sense that the rotors need to be protected? :)
The approved method for checking wear is to weigh the rotors. The minimum weight is stamped onto the rotor hub, so it's easy to check.
Brake pads will be available from GM, and probably from other sources later, as more cars get these brakes (they are also available on the new C7 Z06 as well as the Z/28 Camaro).
Of course, you will still need the specific parts from Superlite, who developed the different uprights and brackets needed to make these brakes work on the SL-C.
A discussion about carbon ceramic brakes on the SL-C can be found here.
You'll probably want to repaint the calipers and take off the Corvette logo. :)