I'd see ordinary batteries as a real plus
I once got stranded in an airport for 2 days - my MP3 player takes batteries ... the ipod crowd were out of juce very quickly - I just bought a new set from the shop
get a couple of packs of rechargable batteries ...
my charger has a mains power supply, a 12V car adapter ... and a USB adapter
and I always carry 4 extra sets as spares
on holiday - I also buy a couple of packs of duracells just in case
battery packs are fine until your camera goes flat ... and you have nowhere to plug it in
if that happens with aa - replacements are easy to find
also - high capacity aa = �8
spare branded batt pack - a lot more that �8