Dokku is _preeeeeetty_ good but you kind of end up messing around on the server eventually to get things working, or fix things, etc.

If you're into that, or have CPU/RAM requirements that would be prohibitively expensive on Heroku then give it a try (I run it for a couple things on a cheap but powerful dedicated machine). If you're just doing something simple it's probably not worth it, just get a hobby dyno and go that route.