This may be true as far as weight with the new hyper lightweight components being introduced. For years people were swearing by factory disc over factory drums in the weight advantage department and stopping power, but it was proven time in and again that the factory drums were both lighter and less dragging, but not as good in stopping. FWIW, A good factory drum set up stops very well, but fades if you are not careful and mindful of how to apply them. Now with these all new ultra lightweight disc setups, you can find both lightweight and less drag effective systems. But one thing to keep in mind, is that these kits may not be for the heavy at heart. In other words, they may not work effectively on a heavy car being that they have limits by the weight of the cars that they are trying to stop. My friends full interior steel Charger with Wilwoods saved a bunch of weight over the factory discs, but also ate through those rotors in no time being that it was a real street car and weighed over 3700 Lbs. On a very light car they may be a no-issue though.
