Hello All. I have been able to get my hands on some new after market batteries that are sold on Ebay, its a replacement battery for the Canon LP-E6. i have also put these batteries through a battery analizer to actually find out how these test up. The results are very concerning. These 2 batteries came with an aftermarket battery grip that was bought for a Canon 7d, the idea of a battery grip is to give longer shooting times right?? Results: Battery 1. To start off this battery would not charge, i think this is due to it not having the chip or the chip may be faulty. This battery weighed 75Grams (Origional Canon is 79Grams) As i could not charge this battery it had to be charged with an aftermarket Lithium Ion Battery charger. This battery would also not work in the camera, it just says that it is unable to communicate with the battery. Total usable capacity was 793mAh, or 37.76% of rated capacity... not very good from a battery sold as 2100mAh!! Battery 2. This battery would charge fine on the Canon Charger, Once charged i thought i would put it through a capacity test. I tested this battery with a 400ma load, this is quite small and would give the battery the best possible chance of giving good capacity. This battery was tested twice, with a full charge for both with sitting time of approx 30mins between the full charge and the discharge test. The capacity of this battery is sold as a 2100mAh battery, the actual usable capacity was 547mAh and 552mAh, thats only 26% of the rated capacity. I did expect this battery to be low because it only weighs 47Grams (Canon Origional 79Grams). Both batteries supplied are identical except for capacity and weight (75g and 47g) If i was to run both batteries 1 & 2 in a Battery Grip i would have a total usable capacity of 1340mAh. Why bother, as the origional Canon LP-E6 has a usable capacity of 1800mAh!!! Will continue to update this post with the outcome as i have presented these results to the supplier and i am currently waiting for a response. I am repeating the tests overnight with only a 100ma load, this will give these batteries the best opportunity to prove me wrong.. So buyer beware, Ebay batteries are cheap for a reason. Cheers. Simon..