For 8 out of 10 people, the XP-G is the way to go. It will give good throw, nice spill and is a higher flux bin than the XP-E. Good overall EDC beam. I would recommend going with the XP-G.
For the other side of the coin if you are a throw junkie and don't care so much about the spill, the XP-E will probably offer a little more throw at the expense of some spill area. XP-E will be less overall lumens than the XP-G.
I have this light and like it a lot.
Here are some beamshots I did with the C2H and a few others. Shows the output on both AA and 14500. You can expect the output to look exactly the same on RCR123 as it does with 14500 (same input voltage). For some idea of the XP-E beam you can look at the Maratac and the ITP A2 - keep in mind to look at the profile only and not necessarily the brightness, as the C2H will drive the XP-E harder than either the Maratac or the ITP in these shots, so I am only suggesting to look at the "shape" of the beam in the XP-E shots vs. the other lights which are either XP-G or XM-L. Also even though the XM-L is the newer emitter on the block, many still prefer the XP-G over the XM-L in a small EDC type light light the C2H.
Very nice little light that despite being around for a long time can still hold it's own. The only downside to this light is runtime is not great, and this may or may not be an issue for you.
For one other reference point if you are still digging, here are some
more shots I did a long time ago that shows the Dereelight C2H holding it's own with larger lights.
Hope this helps somewhat.