Can't beat Surefire. I think there are some competitors now, but seven to ten years ago when I bought all my flashlights, there weren't. That I can't name one serious competitor of Surefire is a testament to their quality --I haven't had to replace one or shop for one since I started using them. I know they have a few though... Wait. FN makes a well built flashlight, saw it advertised in their flier. How it compares, no idea.
Surefire also has a TON of accessories, research and development, and a huge line. They make mini lights for reading maps up to weapon lights for armored vehicles. Biggest of all, the make real weapon lights.
See, if you choose incandescent, you NEED a shock isolated housing for the lamp. A regular light, like a maglite, won't cut it, particularly on high recoil weapons like a shotgun. That fine filament in a light bulb? In a house light bulb? Well, same thing in any incandescent bulb, and when it gets hot and rattled, it breaks easy.
The new LED ones, the Surefire ones with the funny looking lights anyway, don't have this problem. Shock isolation isn't as big an issue.
You do indeed get what you pay for when it comes to these lights. The X200 and similar models are great --well built, light, you can put on a remote switch, some come with lasers, they have a choice between a focused light and a broad beam, and the thing is made very well. I saw them hammer a nail with a working one attached to a pistol when they came out, and that went on their advertisements.
My wife even carries a Surefire light in her purse, and uses an LED one to pick up dog poo (the LED lights are MUCH more conservative on batteries). Unless we lose one, I can't see them ever getting replaced. When we say "they don't make 'em like they used to" well, Surefire makes 'em like they never did in the first place.
I can't say enough good about Surefire. Just like I carry my pistol everywhere I go, I carry my one cell Surefire light everywhere I go too. Only wish was that all mine were LED... Like I said, I got mine years ago before the LED ones were popular. Get LED, go Surefire, you won't be let down.
I put an X200 on a shotgun and use it on a pistol as well... Got it for HD in other words, and it is more flexible than the big ones we used on our rifles for entry work (and cheaper). They make something for everybody, their catalog is like a phone book almost.