I like what Proton has done with Proton Mail and their other services, and I would find it convenient to use them as my password manager as well. Unfortunately, Proton Pass is terrible. I encountered dozens of bugs within the first day of usage, several quite severe. For example, it consistently autofill my username rather than my email into fields that are clearly marked as "type=email" in the HTML.

Resolves subjectively based on whether all of the egregiously bad issues are fixed, and I would be comfortable using it rather than one of their competitors.