Firstfives.org

I've seen, used an orange goop that dries rubbery between the pistons and pad backing plates, to stop squeaking, vibration.

These calipers came apart featuring full size, thin aluminum shims. Tabs for the pins and slathered with what appears to be anti-seize paste on both sides.

As squeaking has never been a frequent problem on any set up I've used in twenty years, are these plates n' goop a good deal, or some hooptee whiz bang
stuff for the trash ?

I've seen those come in pad sets. I'm not a fan of the aluminum shims, I've had them make noise. If squeeking/squalking/screetching is a problem, the goo you spray on the back of the pads and let dry for a little while works great. But I only use it if there is a problem.