Backup gyros - which do you trust?

Richard Kaplan wrote:

Put it where the turn coordinator is located and the put the turn
coordinator off to the side somewhere..

N. F. W.

I think it's time I had a really, really, good hunt for
that post about the Grumman getting flipped upside down
and dumped into IMC after (what was probably) a collision
with an RC plane.

Those Electric and Vacuum AIs come with a get-your-life-back
guarantee they honestly, really truly, won't tumble, never ever,
no matter what, even if I do? How do I test it, in a non-aerobatic
plane not approved for spins?

Cheers,
Sydney