The lockup on my large Apogee is very secure. The full thickness of the lock bar engages the blade tang, and there is zero play to allow the lock to accidentally release. The geometry of the lock is different from the Sebenzas I've seen. It has slightly more tendency to stick, but that makes it even more secure. The Apogee has all the solidity and strength of a Sebenza, I think. Very solid knife, and pretty too.
Harv