I couldn't live without extras-devel. I indiscriminately add whatever I feel like without paying any attention to which repository it comes from. I am perfectly ready to flash when necessary, but rarely need to. I do watch my rootfs carefully after every new install.

I don't think that developers actually use extras-devel the way theory says they do. I think they expect users to use it when it is available.

I hate to say this, but if developers actually didn't want anyone to use their code when they posted it to extras-devel, why isn't extras-devel hidden from testers and regular users?

Extras-devel is just fine for people who don't mind a little risk, I think. The hysterical warnings are way overdone.