Honestly, the 5740 movement, the 240Q movement, is a great movement. But it's past its prime. That movement is close to 50 years old. And in today's world where we fly back and forth, not being able to change adjust the time due to timezones on a perpetual calendar is an issue. Patek really needs to make a QP movement that is capable of withstanding modern usage! And the clients who buy these things are often frequent travelers.