Super Battery for Lumix FZ18

I bought the battery as second battery for my Lumix FZ18. It fits well into the battery compartment and is also just come out easily. The charging time is also about 2 hours as the original battery. But apparently he really has a little more power than the original Panasonic battery, because I can make about 15-30% more photos with this battery. Exactly one can not tell, because you're sometimes more or less flash and more or less playing around on the camera ;-)
Possibly I will report again in a few weeks when I have made detailed experience with this battery!