I was watching a TV show not too long ago that had a do it yourself about taking a .99 cent flashlight and making it just as good or better as this flashlight. It also involved a bulb (that I can't remember the name) that came from Radio Shack. He took a file and drill and took the ridges that are inside the cheap light to hold the AA batteries. He then took 3-3volt bateries and put them in it. They showed the 2 lights side by side and this cheap one looked brighter than the surefire light. It was less than 15 bucks and he then painted it black. I am going to try it for myself but I am sure someone can find the instructions on the net. If you haven't bought this one already I am sure you could spend 15 bucks to try it out and save a lot in the long run.
They were converting a standard flashlight into a XENON light. I haven't seen it done, but heard it was pretty simple.