Pros: Durability, Brightness
Why so expensive you ask?
So it's been posited that this is an absurdly expensive light and cheaper, albeit brighter, alternatives were given. While there are certainly less expensive, brighter lights those arent the only two criteria when purchasing a light. There's a simple reason that this light is so expensive: IR capability. For those that haven't been in the military it's an invaluable function when using NVGs or needing a backup for covert illumination - whether for marking a target or for troop movements. There are other options out there like external filters, but that's just another piece of gear that will inevitably be lost or broken when needed most. The internal IR eliminates that possibility. Surefire are awesome lights and are all I use, particularly for weapon lights.