Read somewhere that old school trim carpenters did the glue size trick on MDF edges too, something about the glue stiffening up the fibers so they cut clean instead of mushing. Sounds like Ray and those guys figured out the same thing decades ago while the rest of us were out buying fancy sanding blocks.

I was right there with you thinking they were a waste of money until a buddy showed me a video of a guy popping a window with a center punch and never setting off the motion. Total game changer for me lol. I haven't had a ton of false trips yet but I did have to move one away from a vent after it kept going off on heat cycles.

That $1.89 bag changed my mind too, dry beans aren't worth the fuss.