I take the standard to 720p / 100 FPS that has the problem that in fact the battery lasts barely ran to the two hour mark. So I have looked for new sources of power.
1. The large battery pack was too expensive. Moreover, were the reviews, particularly the reviews, not really promising.
2. The standard GroPro battery was also not favorable.
Both GoPro battery also had the disadvantage that I have to charge the batteries via USB to the camera. Therefore, a separate charger was very tempting. At the risk of "who buys cheap, buys twice" I got me this product picked out and tested.
Abdominal pain were: getting hot / vll goes in the camera broken / lousy runtime.
All this has not materialized. At runtime, I can not really say what. The standby times vary, sometimes one makes series images, even video, sometimes it is simply. It may be that this article has a lower duration. However, I'm interested in the little, because I now have three batteries and can change ;-)
There were no heat issues, the charger loads faster than the camera (also the original GoPro battery). I now have enough power for brief 5-6 hours of recording.
Next issue:
As long as not holding the SD card, so I also had to get a new me there: p
[UPDATE]
I do not use the battery for some time now. Meanwhile, I prefer these batteries compared with the originally supplied small batteries! These are gradually weaker. Funny. I still bought the above BacPack because there are situations where I can not change the battery (in the water). Nevertheless, these batteries .. I find better than the original small batteries.