Both are winner. One is the winner for one group of users and vise versa.
Granted, both are good light.
In additions to Al's good points on G2, G2 also allows higher output lamp option and optional conversion kit to change it to a rechargable light (with a little less output than its standard lamp).
Scorpion has spare bulb stored in the light, this is a very important feature (at least for easing my mind). Its bulb cost a lot less since it doesn't require extra assembly.
Unlike the G2, Scorpion tailcap switch will be safer from accidental switch-on that drain your battery until you feel the heat on your butt. Scorpion also has adjustable light beam capability that might be helpful for some users.
See, the same features could be flaws to different groups of poeple, again and vise versa.
Alan Chan