It's basically just two horns, the noise outside is not as loud as a real exhaust, but it's still pretty noisy inside the car. The app can switch between different sounds, which is indeed fun, at least making my P300 feel like a real sports car.
With the active exhaust on and the engine still running, I removed fuse 15 and revved the engine in place to test it. The exhaust sound did change, but the difference seems minimal. Would this cause power loss at lower rpms?