Good enough for how I drive. I usually replace pads every 100,000 miles and rotors every 200,000 miles. I'm a defensive driver and rarely get into a panic situation. You can definitely lock up 10" drums with most tires. Maybe not yours but in everyday driving I don't need 11.75 pin calipers. The 11.75 rotors are on my brothers 67 Barracuda that is converted to 5 x 4.50 bolt pattern. Not worth the time or hassle for me and I doubt the OP needs to upgrade the brakes to get his Barracuda going if he has an 8 3/4 rear and 10 inch brakes.
