I've been told that to 2 best batteries to use for most any LED Saber are the Duracell Ultra or the Energizer e2.

Which one is better to use ? I've heard the e2 because it has an on-board battery checker to see if it's dead or not, and this is handy because you're supposed to change the batteries before they get too low and damage the electronics or something to that effect, I dunno.

All I know is that the Duracell Ultra's are less than half the cost of Energizer e2's. Any input would be welcome and I hope this is the right forum ...