Absolutely inadequate !!

I had bought the "Varta Power Accu .." for my compact flash. According flash manufacturers there should be at least 2500 mAh. I quickly found one. The Varta batteries were well tested and promised 2700 mAh. Shipped quickly, I have properly charged and inserted right after that. However, even though the flash was used for less than 20 photos, then lay in the camera bag, the battery was empty the next use. It is easy to imagine how annoying that. I've even tried four more times, but then I gave up. Even if the batteries were not used at all, they have discharged. This is absolutely insufficient, especially in the price range. I have then bought batteries from another manufacturer (Duracell) with 2500 mAh, which function to this day perfectly!
Who is looking for a reliable battery, which should not to Varta Power Accu NiMh ... grab!