I love it. In fact, I ended up getting a second account for small business.
For Linux, I couldn’t really tell you how well it works. It works well with Thunderbird on Windows and Fairemail on Android. But I usually use the web interface, which works everywhere 😀
I use DavX on android to sync my contacts and calendar without any issues.
The price is great, and I appreciate their transparency and privacy-respecting business model.