[mitchellpkt]

For personal correspondence, I've exclusively used Proton Mail for the last 7 years or so. I have been happy with it, no plans to change. I migrated from Gmail, and initially set up message forwarding so that I would still receive emails from old contacts. A few years ago I connected my personal domain with Proton so that I can send and receive from @mydomain.com - their setup wizard was quite helpful.

I've also used the calendar, drive, and VPN products. They all seem to work well in my experience of light day-to-day personal use. For the email and calendar products, I interact with both other Proton users and people using other providers (Google products, company-administered systems, etc) and it seems to integrate seamlessly. If you use Google docs/sheets/slides, it can be convenient to set up a Google account tied to your Proton Mail address, with no associated Gmail addresses.