Hey I'm happy you gave Panelbear a try! It's always nice to hear someone is using what I've built.

Regarding the free tier, I decided to offer it after hearing many people saying "I wish there was a free alternative for a blog that gets less than <50k views per year" :)

There's no strings attached. Only volume limits and shorter data retention (to prevent my AWS costs from blowing up).

About traffic spikes (eg. reaching the front page of HN): even if you go over the limits, the system won't start rate limiting you for another 72 hours - that way you won't lose data during traffic spikes.

Hope it helps!