Looks interesting, but once you've entered all your email addresses, you'll receive one security issue after another and nothing works. Even your account is blocked for a while. If you want to send email, they say you send spam and nothing works. But maybe they intended like this. After all you give your information to the Russians.
I've been using Yandex mail as both personal as well as business mail for couple of clients. Connect your domain, and after a couple of verifications you're set. The interface is better than gmail, with no ads, and plenty of options to change theme and layout in one click. Unlike gmail and outlook, space is not limited and expands as you need. You can also use IMAP/POP/SMTP with any email client. In terms of server response time I've tested it and found it to be as fast as any--200ms. This is usually better than regular hosting services. In my experience, Yandex is a very good option. Yes, some places you can encounter notifications in Russian, but nothing that really interferes with the actual email service. So, I can recommend yandex mail for personal as well as business purpose.
If you value your email do not go with Yandex. They have no customer support and their system does not operate like any normal email. You will be very disappointed.
After creating an account I couldn't send a single email. It says it couldn't be sent becuse it looks like spam. That's sick.