In two years I’ve had no problems with the service. It’s rock solid! I was able to import my contacts, calendar and migrate all my email from Gmail to Fastmail with the help of the Fastmail Migration Guide.
I also setup hosting for my own email domain. With Fastmail’s ability to have aliases I added extra email addresses at my Fastmail domain and my custom domain. With my custom domain, I added wildcard or catchall aliases to ensure any address used at my domain would be received into my account.
I still have accounts with other providers, but I use FastMail as a central location to read and reply to all my mail. I set up identities which let me send mail using the other address, and to optionally fetch the mail from the other mail providers.
I organize my email with folders and rules and if I need to search for something Fastmail’s search is blazing fast.
Fastmail’s web interface is super fast. IMAP setup in third party email apps is seamless as compared to Gmail. Fastmail doesn’t offer a desktop app for the Mac but you can do as I did and use Fluid to make your own Fastmail desktop app. There is an iOS app in the app store which is a skin of the web interface. I use Spark.
And yes, Fastmail has Two-Factor-Authentication.
If you’ve been thinking about leaving one of the free email services and want to better protect your privacy then give Fastmail a try. You have nothing to loose with the Fastmail 30 day free trial (no credit card required).