So, what’s your idea for a modern “propulsion system” that will magically appear under everyone’s cowling? Yes, unleaded fuel is unavoidable at some point, but it’s still a joke. If it weren’t for states like CA, or dare I say THE state of CA, we wouldn’t be worried about 100LL. Let the recent fires in CA be your indirect guide, and do not automatically follow the self-anointed geniuses. I have resided in CA for all but 2 of my 63 years. It used to be a decent place to live, but today it runs on perpetual dysfunctional agendas.