I took a look at Tor Mail today and have some serious questions about what's going on with them.
Hosting IMAP and SMTP servers isn't free and they neither have ads nor do they charge for the service. Where is the money coming from?
Can anyone estimate how much does it cost per year to provide the service? They don't even ask for donations.
They could be wealthy and generous.
They could pay the hosting by selling some data they can collect. Who communicates with whom and some mails without encryption.
They could be run by evil people.