Today I made a short term test.
I got the GoPro Hero 3 Black Edition. My film adjustment was 720p 60 W.
The original battery lasts 1:32. Both Pattrona batteries hold exactly 1:40 (THROUGH filmed).
1:30 is obviously not a very long time for filming but compared with the original battery and the price, I can only recommend the replica.
Thus, the replica is only half and keep even few minutes more (also by about 130mAh more).
Long-term testing is still pending, will update my entry in a few weeks.