sunscreen snobs of reddit, i summon you: whats the best SPF you swear by and why?

I've fallen into the SPF rabbit hole and now I'm insufferable at parties. So let's settle some things:

- what are you actually using and why should I care

- what do you look for — or are you just vibing and hoping for the best

- what's an immediate red flag on an ingredient list for you

- European filters vs American filters — is the US just decades behind or am I being dramatic

- SPF 30 loyalists: explain yourselves

bonus question: has anyone actually dumped a brand over sketchy ingredients or is that just a thing people say online

no wrong answers, just looking to be influenced and mildly judged for my current choices