Flawless so far in connection with Apple Watch Ultra 2 and series 9 during HIIT and running workouts. Worth the money.

In comparison with the Garmin Fenix 6 Pro, the heart rates are almost the same with the Polar!! The Polar is more stable during tests like Burpees, for example, which involve sudden increases!! It's worth its money!! The Polar app needs some improvement!

I give it **** because it is excellent in its measurements with accuracy and very good build quality. In contrast to the chest strap that I simultaneously use and compare with a reputable brand, the Polar OH1 has better responsiveness to heart rate and so on. Its main disadvantage is that if you do any exercise in a pool, during dives or using TRX-type straps, it comes off its position and you are forced to put some kind of armband on it from the outside to keep it stable.

I have it for almost a year. If it wasn't for this delay of almost 5-7 seconds, I would give it 5 stars. Otherwise, together with the Polar Beat app on my phone or connected via Bluetooth to a sportwatch, it is incredibly convenient. I have no regrets at all, but it is a bit pricey. Used for running, cycling, and the gym.