Yes, on the 757 the brake accu works for a few hours, only good for a quick turnaround. Our Airbusses have 2 piston systems on the brakes, but on the other hand we can't even put on the parking brake. The brakes tend to be a lot hotter than on the 757 after landing, and by putting parking brakes on we get a lot of sticky brakes. (pistons unable to release when putting brake pedals off)