1) The hefty surcharge for the Tri-zone model is not justified. Buy the cheaper, rotating model and just put a tri-zone head on. To have 4 pieces for ~ 12 Euros, which saves you the well 30 euro price difference for the 2 beigelgten Tri-zone heads.
The only difference lies in the travel case, the other has stampings. But you can also with life when the heads do not hold up well to 100% as it closed anyway travels with it and it really is not important whether the head is in its holder or beside it now.
2) The app is immature and senile. You forget all the settings regularly. I've tried both the iOS and the Android app.
3) The promised storing values up to 30 days in the brush head with subsequent submission to the app is a tough lie. Nothing is saved.
4) The app transmits your usage data (according to well camouflaged approval but also only) on Google for analysis. Thank you.
5) The app is totally overwhelmed when a cleaning process is not counted from 1 second and is completely messed up with the times.
6) The brush disturb apparently each other in the Bluetooth transmission. This can not happen actually according Bluetooth standards. Oral B still manages the strike technique.
All in all, this brush nothing better than mine in 2010 bought brush without these Bluetooth nonsense, only it costs much more.
