On the other hand the paid version is no fuss, affordable and works great. Its much cheaper than fiddling with how to selfhost it. Not sure what bugs would be in paid that are not in the self hosted one. It´s same thing.

Bugs aren't in their code. It's the way they've configured their server that hosts the .js. Their headers are fucked up so some browsers will never load the .js correctly, and you'll never know about it. So your stats will never be remotely true.

What bugs did they refuse to fix?