Econo rotors are not nearly as good as factory rotors. Premium rotors may be as good as or better than factory specs. Thickness should be about the same. The difference is in materials (quality of metal used), quality of casting, quality of machining, etc. It is not uncommon for econo rotors to need machining right out of the box. Econo rotors may be OK for a very gentle driver, but I would not want them on my car.
