Surefires are just a total pleasure to work with.
Every detail is perfect.
My first SF was a C3 Centurion HAIII with P90. It is still one of my most used flashlights, now I own 14 Surefires.
Now its gonna be a little tech-talk: nearly all SF flashlights operate on primary CR123A batteries.
A C3 Centurion needs three of them, and burns through them in one hour in the best case(!), worst case (with the optional ultra high output lamp assembly P91) this is done in just 20 minutes....
At the same time as you buy your C3, you'll need to buy a few AW protected 17500 rechargeable Li-ion batteries and a good charger. Then, you'll have "guilt free Lumens" from the start, and... you'll really start to USE this flashlight!
Tired of the incandescent lamp assembly (LA)? Just take any D26 dropin, either LED or another incandescent.
"D26" refers to the size: it is 26mm in diameter.
The most versatile SF flashlight I know of, is the U2 Ultra. This one ranges from 2 to 100 Lumens, has an unbreakable LED, and you can choose the brightness with a very easy selector ring. Runtime ranges from 175(!) to 2 hours, depending on the setting. If I had to sell all my flashlights except one (which are more than 50) the SF U2 Ultra will be the one to keep.
It has an excellent combination of throw and flood.
The only disadvantage is, to me, the color of the light. It is just the ugly blue-white color nearly all LED-lights have.
This is the main reason for my frequent incan-use. The color of the light more than makes up for all disadvantages, like high power consumption (read: short runtime), fragile filaments, not shock-resistant, and limited life. Don't get me wrong: LED-lights do have their place in my collection, and I use them regularly, but the simple, no-fuss, pleasant-to-the-eye incandescent lights are my favorites. The best, in this category, is undoubtedly Surefire, but Wolf Eyes is a good competitor (M90 Rattlesnake, M300 Lion).
Timmo.