Agree with Julien. The HR monitoring side of the Surge and Charge HR leave a LOT to be desired. Hopefully Apple will be able to implement something more efficient than what Fitbit has done. According to both the Surge and Charge I'm the fittest man alive. I can finish a complete weight circuit and a 45 min cardio session and never have my HR go above 89 🙂
I'd love to see a pulse Ox meter as well, but I'll settle for workable and accurate HR data.