Just that their support rubbed me the wrong way. I wanted to use their commercial offering but it had a bug which stopped my site returning any telemetry. They basically refused to do anything about it, and that was a big red flag. With Javascript analytics you need to know that it is returning for 100% of compatible clients with JS enabled, otherwise you are missing valuable metrics.

Google Analytics worked fine on my site. Plausible's script causes a script error which killed it dead. It's only a bug in their commercial system. I spent hours debugging it myself and found the bug in their system. Seeing as it's a bug only in their commercial offering (not their open source one) I said "throw me some free credit for my time" and they said "no thanks, I'm sure we'll figure it out ourselves one day, don't worry about it". After that I didn't want to touch their product.

I also pinged Marko (co-founder) on Twitter and no response there either. So, honestly can't recommend their paid service at all.