Dukester, you mentioned a good selection of lights,....firstly I must apologise, I have the newer X5T and not the original X5, perhaps there is a difference. My problem is that I judge light output of the X5T against my Surefire flashlights, (G2, 6P and 9P) not a fair comparison. I carry my X5T all day in my pocket at work, maintenance work in a large factory environment, confined dark spaces etc. The G2 is far too bright with short run time. The X5T has been nearly perfect except that it is not quite bright enough in some situations. I really would like to stick to the size (under 1" from one end to the other) with better run time than the G2.