Battery power is the MOST important thing for a digital camera.
Without adequate power then the thing is and expensive heap of junk.
My D1x was a chore to use and maintain. In the 18 months I owned it, it chomped it's way through €2,000 worth of En4s and DCBs delivering some 40,000 exposures. Against this my year old D100 has 1/2 this done on the battery that came with the camera.
My pic below is an illustration of the difference in power requirements and the bulk and volume necessary to keep a D1x on the road for even a short while.