Why not get a Led drop in?
Brighter, longer run time, Led last longer too.
Can use 2 cr 123 or 2 Rcr 123.
I don't like the color tints from LED ...however I'm hearing that certain LEDs have a really good color tint, so I'm going to get the Malkoff M61 in a few more weeks. Thanks!
Make sure you get the new Nichia one then.
I've tried the P90 & 91's in a G2 using 2x123As and they run dim, the P91, even more so.
Not sure if there's any harm in underdriving the lamps, but no real benefit either. I didn't run them long enough to measure a runtime.