As many have already stated, this model has serious flaws. I went through three of them under warranty and truth be told needed a fourth but the replacements were all based on the 1 year warranty of my original purchase, not the subsequent replacement. So translation, not a single one lasted a year.
The band begins bubbling near where it attaches. (I was asked if it had been in any extreme environments or temperatures which apparently was believed to be the cause. - Nope, live in a dry, mild heat area.) Once it has started bubbling it's only a matter of time before the band completely starts to peel away and it becomes useless.
I do however recommend the Charge 2 HR. The bands are replaceable, so lots of affordable options (some of which are very nice) on the parent company. The unit is much more well built and I haven't had any issues after nearly a year. And I really like being able to swap the bands rather than always being stuck with a silicone one that just looks tacky.