I got started with handheld tactical lights with a SF (SureFire) 6Z, then a C2, then an M3, and then a A2 (Aviator - 3 low power LEDs around a Xenon bulb). My A2 has red LEDs. And some where along the way I picked up an StreamLight M3 WML (weapon mounted light) and a SF X200. All these lights have one thing in common, a blinding bright, sharply focused beam.
Then last Spring my projects class, as a project, evaluated 20 tactical lights for intensity and rundown characteristics. But more impressive to me was the subjective tests. The students got in a dark room here at school, turned on tac lights one at a time and each student ranked the lights according to what they saw.
All but one student gave the SureFire L2 a poor ranking because it wasn't as sharply focused as the others. I couldn't get that one student's opinion of the L2 off my mind (which I disagreed with BTW), and also because it is a dual intensity LED light, I started carrying the L2 as a personal light.
I carried it regularly and used it for just about all my lighting needs. I often "examined" a dark room before I turned the lights on just to see what I could see with the broadly focused L2. I regularly compared the low intensity and high intensity beams.
Then one night, I decided to revert back to my Streamlight TL2 LED for its compactness and more intensely focused beam. The first time I turned the TL2 LED on in a dark room, I was surprised that my reaction was, "I can't see with this light!" The beam was full brightness, focused as always, but the problem is, it has very little light in the "lobes". In other words, it only illuminates the area covered by the focused beam. I had grown accustom to the L2's broad beam that really lights up a room, "wall to wall".
That's when I realized the L2's broader focus was much better than a tighter focus indoors or at shorter ranges. I got the same effect when I switched on my X200A this weekend. It is a tightly focused beam and I quickly noticed how narrow the beam was - just like most other tactical lights.
So as a result of about a year living with the L2, I have concluded that the broader beam is generally better for "inside" and short ranges. BTW, the L2 does have an Achilles heel, if you run it for 20 - 25 minutes continuous, it will overheat and get so hot you can hardly hold it and it starts blinking.