I was drooling over one of these Petzl e+LITEs as a replacement for my Petzl Tikka Plus that's in my hiking daypack to save a little weight, but then I read the specs on REI.com and they scared the heck out of me.

Acceptable:

Weight (w/ batteries)
e+LITE: 1 ounce
Tikka Plus: 2.7 ounces

Half life brightness (70 deg)
e+LITE: High: 7.2 / low: 7.4 foot candles
Tikka Plus: High: 17.6 / low: 11.5 foot candles

Half life brightness (0 deg)
e+LITE: High: 7.4 / low: 5.2 foot candles
Tikka Plus: High: 9.2 / low: 6.3 foot candles

Battery life at 70 degrees
e+LITE: High: 5 hrs. 8 min. / low: 5 hrs. 15 min.
Tikka Plus:
High: 22 hr. 33 min. / low: 68 hr. 45 min.

Unacceptable:

Battery life at 0 degrees
e+LITE: High: 4 min. / low: 3 min.
Tikka Plus: High: 7 hr. 28 min. / low: 23 hr. 51 min.

I hope that's a typo, because the last thing I need when I find myself unexpectedly trying to hike back to the trailhead in the dark and cold is for my battery to die on me in three minutes. For now, I'll skip the e+LITE and stay with my Tikka Plus (which I love), or maybe switch to a Zipka Plus for the slight size/weight savings.

As a side note, lately I've been using lithium batteries in all of my outdoor electronics (GPS, etc.) for the weight savings. Petzl says you should only use alkaline batteries in their headlamps because lithium batteries can cause the headlamps to overheat and damage the LEDs. I emailed Garmin to see if there was a similar potential problem with my GPS, and they said lithium batteries were fine. Does anyone else know of instances where it isn't safe to use Li batteries?