I remember this from your YouTube video! I came across it when I posted my own video diatribe about Boyds and the decreasing quality of their non-wood parts. I still prefer something that would positively lock in place so I didn't need to worry about losing a small, $30 piece, but this idea is solid. Sharp Shooter Supply Axis stocks have a similar feature, but I believe theirs acts as a front pillar as well.

All in all, I don't mind plastic locking points for the magazine. It's the plastic bearing structures for the action screws that bugs me.