In each of our three cars, I keep (at least) two lights in the gloveboxes. One light is a 2x123 powered incan light (2 are SF G2 with clickie switch mod, one is Brinkman Legend), and the other is a MiniMag with either an Inretech LS led or Opalec Newbeam drop-in.
My criteria for glovebox lights are that they must take lithium cells, so the lights can sit unused for five years and still work when I need them, and I need one to be bright enough with at least an hour runtime for working on the cars in emergency situations, and the other to be LED (no bulb to break)with at least several hours runtime. I'll probably eventually add a single cell, single (5mm) LED light for low powered needs like reading in the car, either a CMG Sonic or Dorcy 1xAAA, especially since Lithium AAA batteries will be released later this year.
Another criteria is that the lights need to be inexpensive because I'll need three of each (and we may be getting another car before long, so four of each then), and we have experienced vehicle break-ins in the past (the thieves stole Maglites in each case), so I don't want to have $200 worth of lights in each car
-Keith