Keeping backup equipment?

I recently had to send my amplifier in For service. In its place I picked up a used Schiit Vidar to tide me over. 
So now that I have my main amplifier back and it seems to back to making me happy I’m wondering if I should keep the Schiit or sell it. On one hand it makes sense to have a backup ready to go, on the other my main amp has
been flawless for several years. So it sort of seems a waste and maybe someone, like me, may need one on the cheap.

so for those running separates, do you have backups stored away for emergency’s?