The lock mechanism is holding up fine. It's a very simple design and it appears to be very robust. There will be no adjustments needed to keep it working as it should for a very long time. The only possible failure I can anticipate would be the fracture of the torsion spring, but I would expect that would be a very rare event which would only happen after many thousands of lock/unlock operations. I also think the lock would still operate in the event of spring failure, although vibration might cause the shaft to rotate to the unlock position with no spring pressure to hold it in place.