I do agree that heroku, while not cheap, is a value for what you get.

But I wonder if that comparison "I think Heroku is a perfectly fine option until you reach the point where you could hire a full time dev ops" is actually one anyone makes in reality. A full time ops person is going to cost way more than $100 a month, quite a bit more than several thousand a month in fact. Are there really people who would go with heroku until they're paying $5 or $6k a month or more, and somewhere around there (that's a lot of heroku), say "Gee, _now_ we're paying enough (barely) to hire a fulltime person to manage the servers ourselves, let's switch everything to that."