I did check it out and it looks really good. As opposed to some other comments, I don't have a problem with pricing (my SaaS is a healthy business and I gladly pay for quality).

But using this solution would mean loading third-party JavaScript with third-party trackers. Which for many reasons is a complete non-starter. I'm quite happy to have a site with zero third-party scripts/trackers.

So, call me when I can send the events myself from my code :-)