I use Fastmail for my personal mail, and I don’t regret it, but I’m not quite as sold as you are, I guess maybe because I still have a few Google work accounts I need to use. Spam filtering in Fastmail is a little worse, and the search is _terrible_. The iOS app is usable but buggy. The easy masked emails are a big win though, and setting up new domains feels like less of a hassle with FM. I don’t regret using Fastmail, and I’d use them again for my personal email, but it doesn’t feel like a slam dunk.