Leaded race fuel only, never had one die. I replace it every couple of years, just for piece of mind. Have run one for 8 years? Actually, I have one start to flake out.
Yeah, leaded fuel can slow them down but using non sensor safe sealers will kill them dead PDQ.
Don’t ask how I know that. In fact, I have two new O2 sensors sitting on my desk to replace one I killed and I’ll use the other one as a decent backup.