For something in web3, it's surprisingly easy to use, feels a lot like you're using a regular email client. So A+ for simplicity. Unlike regular email: you can send messages to blockchain addresses as well as [name]@mailchain accounts.
Bonus points:
+ Product was built to respect your privacy, no personal data leaves your local machine without being encrypted first.
+ It's an open source protocol with public SDK for other devs to build ontop of.
+ Public good quota of free messages.
Highly recommended. 👍