Yes, it’s been very reliable. IME, the vast majority of people who complain about deliverability issues are spammersmarketers. They set up their own servers, send out a bunch of spamnewsletters, then complain that they get marked as spam. I don’t have much sympathy for them.
Of course, I’m not saying that it never happens to legitimate email, but IME, that is increasingly rare, especially after setting up DKIM, SPF, and the like.
It also gets better over time as your IP gains a better reputation.






It means I have an old desktop in my closet, that I use to manage my own email. Here’s an example on what it takes to set it up: https://linuxvox.com/blog/install-and-configure-postfix-and-dovecot/
http://www.mutt.org/ is how I browse, manage, and send my email