They feel great with the car not running. the pedal holds pressure really well. It does not bleed down. I have no leaks and i am not loosing fluid. As soon as you start the car it falls to the floor. The brakes work with the engine running but not well! if im driving 10 mph and i lock them up. The pedal goes rite to the floor and the car will brake with like 25% of what it should. I have a 11inch dia booster with a cast matser. I think its gota be the booster cause why would the master hold pressure with the car not running?