In reply to LA1KHA:
Yes, I have also found it hard to find data sheets for batteries. It seems that manufacturers like to keep their information secret. I found it similar when looking for specifications for outdoor clothing. For example, try having a look at the data for Gore Tex fabric. You have to look very hard indeed to find the information on how waterproof the fabric is!
I have found some indications of PP3/MN1604 capacities.
Duracell ProCell - about 550mAH
Energizer Industrial - about 600mAH
Of course these numbers don’t mean very much, it depends upon how the battery is used (tested).
I think I will just go with the Philips Extreme Life, as this has proven capability!
I will post some pictures soon of my rig. I don’t have my camera card reader with me at the moment.