I have a Fitbit Charge 2 and have had it for almost a year.
To be honest, the only reason I got the thing is that my GP (General Practitioner) rather strongly suggested it as she was concerned that my resting heartbeat during our quarterly exams was too high.
Anyway, I purchased the damn thing ($149.00) at the time.
The day after I got it, I decided that I absolutely HATED and DESPISED the El-Cheapo plastic wristband that came with it and I purchased upgraded to a magnetic metal mesh band...
The band (later on I purchased a Gold Band for when I am dressing up for the evening) is well worth the extra if you are committed to wearing Fitbit as it will adjust to the precise size of your wrist and it is also BREATHABLE.
Just search Amazon for Fitbit Charge 2 bands.
But as usual, this time of night I digress.
Now I rather like the thing. It stores my heart rate information for 90 days and I set up my account and gave my GP my password so she can log in and get all my stats when she likes.
Regarding the resting heartbeat?
I told her from the start that my resting heartbeat was only high in the doctor's office since I was already Pissed about having to fight city traffic to be poked and prodded by a doc and the vampires that take my blood!
Also, I use a fancy ass CPAP at night for my sleep apnea that log's my sleep data into the internet.
Turns out that my sleep doc can watch my FB results, compare with my CPAP and adjust remotely if needed.
I also think it is kinda cool that when I get a call or a text, I get an alert on my FB via vibration and display.
Kinda really digging this thing right now.
Seems that I more than got my money's worth!