@napoleon The Oneblade V2/Genesis does accept despined Gems without notching for most people I’ve heard of who’ve tried it - you’re the first person I’ve heard of for whom they slip out.
It’s all I use these days. It works great for me.
I know, and I bought it with using gem blades on my mind. I've tried the V1 and had no problems with unclipped gems but tried the gem on my v2 and it slipped out. Or better yet, slanted out. Just doesn't jave enough friction on the sides to hold it in place.