Bests & Worsts Reviews from Amazon

I really wanted to like my Fitbit Charge 2. I recently had a heart attack and needed to accurately track my heart rate. So on 1/30/18, 3 days post heart attack I ordered this product, having successfully used the original Fitbit Flex to count steps. Less than a week into using the charge 2, the hourly reminder to get up and move went away. I tried everything recommended on the website and blogs to recover it, short of returning the unit, without any luck. I was less than thrilled. I also was instructed to walk a certain number of minutes 3 times/day without my heart rate increasing more than 20 beats per minute for a few weeks. I used the Fitbit Charge2 to monitor this. I began Cardiac Rehab exercises in a medically supervised class with 1 staff to 2-3 patients. We are hooked up to ECG's and have supervised workouts on treadmills, cross trainers,recumbent bikes, etc. Staff monitor our target heart rates via the ECG's. It is crucial for heart attack patients to stay in their target range. To my utter dismay, I learned that when my heart rate was at my upper target limit of 137 per ECG, my Fitbit registered 86!! The next class was no different--137 via ECG vs 94 via Fitbit! This is not acceptable, to say the least. If I had not been hooked up to the ECG, I could have had serious consequences from upping my exertion based on a Fitbit reading alone. My plan was to use the Fitbit Charge 2 as I recovered and did Cardiac Rehab, then use it to safely do my annual hike that begins a mile high with a further 2000 ft. elevation gain, a strenuous hike. Now I have lost all confidence in this expensive product. Unfortunately, I became aware of the studies about inaccuracy after I purchased it. Live and learn. .