DATA POINT
I had the metal latch/strap on my old Ameri-king crack and fail at last annual, so made a new, heavier one. ( not just Velcro fails!)
My new Pointer skyhunter 406 came with the Velcro strap, which surprised me, as I had read about the findings of these failing by tearing, or simply never being cinched tightly enough to keep the ELT in position thru impact forces.
I understand that you'd want to be able to quickly remove the ELT after a crash, but frankly, all the darn connectors for antennae, remotes, and GPS make this almost impossible without removing the seatback, and using a tiny screwdriver to remove a serial connector.
Regardless, I added a big hose clamp around the entire thing, with a thumbscrew for removal without tools.
If I'm in a real hurry, I'm hoping the 3 wire plugs will shear off somewhere non-lethal.
In true aircraft redundancy fashion, why not just use two, and say we must inspect & replace annually or as needed.