I've never used it, nor do I know anyone connected to it. From what I've seen on their site, looks like good stuff.

Checks off all the boxes of which I consider green flags for high quality toothpaste.

They make the claim that lower concentration hydroxyapatite could be just effective as higher concentration, the former is reflected in the price.

Tbh, I haven't seen any literature on effectiveness of hydroxyapatite at different concentrations. Just that nHA clumps up, and in my mind, not enough nHA might mean that not every surface gets covered 🤷‍♂️