OK here is one thing that might fall a little short. The Hinderer button is used on the ZT 300. It purpose is to stop the lockbar from being sprung over while unlocking it. It ALSO stops the lockbar from moving up and down, as you grip the knife. (remember that "hard use" knife..this might be way way over kill, but thats what you want in a "hard use" knife.) Anyways, the ZT button is not thick enough to stop the up and down movement. Not that is a big problem of anything. Just its not the SAME as a XM. Honestly its not really a big deal, if I grip the ZT 300 I can't get much movement at all. But it is due to the thick lockbar, not the button. Here are some pics, they might help my case better.
See how when locked up the XM's button will stop the bar from moving up? (think gripping it as hard as you can, the lockbar will not move up at all! Due to the button.)
The ZT's button is thin, and misses the lockbar when locked up.