Back before I discovered the joys of external DVD batteries, I ran my unmodded R-44 exclusively off the internal AA's with, usually, just two channels of phantom and a pair of 414's. Running like that, I would consistently get about 3.5 to 4 hours of runtime before the battery indicator on the R-44 would tell me it was about to die. Since edtyre is alluding to getting about 6 hours using his solely as a bit bucket, it would seem that it has a lower power consumption in that mode. Not a scientific comparison, YMMV, etc.