Ask HN: Which email client do you use on Windows?

It's really time for me to move on from Outlook, the amount of glitches is becoming unbearable (it regularly crashes on routine operations, like when I try to add or delete accounts, or even just on meeting reminders). My requirements are:

* decent support for multiple accounts

* Support for IMAP as well as Exchange

* Exchange calendar sync, all other features are kind of optional (lean would be preferred)

I tried those alternatives, but none seem to do quite what I want:

* Windows Mail: I actually really like the app, it's leaner and faster than Outlook, but it has one major bug on my machine: it's using the same "Sent From" name on all accounts and doesn't let me edit it. I found an blog post describing the same problem and how a reinstall helped them, but for me not even that does the trick.

* Thunderbird: this would be my favourite, but it doesn't support Exchange