Among the batteries:
I use this system already successfully in my GORRO Hero 3. The batteries are similar to the original. value for the price anyway 5/5 stars
Charger:
basically good, but be careful in this release. The batteries fit properly and the wrong way into (on the head lying). Is only the wrong way round but loaded correctly. When it comes inserts the correct direction on the C line of the battery, a GND terminal of the charger. That's not good for the battery. Unfortunately, you realize that just because the charging light does not start. Because that would really be avoided, here deducting 1 star.
Otherwise recommended.
