Not sure if this has been mentioned, but I just discovered that my X2 has a great new use. I’ve had the X2 for a year and a half and I’m loving it–I have exercise-induced Left Bundle Branch Block and my X2 has been invaluable in showing me (on the ECG) exactly when I get LBBB, which allows me modify my training and medication schedule effectively (I’m a 62 year old competitive speedskater, and yes, I have a cardiologist). I’ve been using my Garmin watch for measuring overnight Heart Rate Variability to watch for overreaching in my training, but AI suggested that using my X2 for 2 minutes in the morning right after waking up is a much more accurate measurement of HRV (wrist sensors are notoriously inaccurate in measuring HR). I’ve been doing this for a few weeks now, and it gives me a great “finger on the pulse” (pun intended) of how my recovery from workouts is going and whether I need an additional day off. X2 is such a great tool!