I've been using Tuta since 2016, on paid plan since 2019.
Outside a single longer outage early on I had nothing but good experience with their service. Granted, I only care about email and calendar (the only two products they have at the moment) but both work without any issues.
I use that exact stack. Bitwarden for 3 years Mullvad and Tuta for one. Can’t speak to their ethics or anything I wouldn’t know. But the quality of service has been great for me at least
Tuta mail is garbage. Used it for over a year and the search was terrible event when using the exact text from the mail. They also deleted my account despite me actively using it.
I use Tuta, and while the search kinda sucks, it's good enough, you just need to make sure you have all mail downloaded that's being searched (last 30 days IIRC).
I picked them because they have similar privacy as Proton with lower prices and features I like (i.e. 3 domain names).
Also curious. I left Mullvad because they stopped supporting port forwarding. Proton seemed like the best second option privacy/feature/price wise at the time. IVPN was touted highly around that time, but it appears they have also phased out port forwarding
for mail, Mailbox.org (originally I said posteo but I was unable to get the payment to go through. idk why). For drive, calendar, contacts, passwords, I'm working on setting up nextcloud but it's not ready yet. I still have a few months before I'm downgraded. for VPN, I'm still looking for alternatives.