@Egika I hadn’t considered the points you raised (watch on the left vs. right wrist and the bike). I have to say I agree with them—thanks. With cycling, the distances are usually so great that I’ve never really compared the readings; I actually find it very precise. However, for hiking and ski mountaineering, I find my Vertical 1 less accurate than the 9 Peak, likely due to the sensor’s position. 9 peak pro instead has the sensor in the same position of vertical but only two little holes, and I find it a little more precise (my girlfriend has it) for uphill, gps vertical is better