I just used my light on a recent wreck penetration dive and also night dive just last night, and it was great! On the wreck dive I was able to light up the entire engine room of the Sea Tiger, and during the night dive I was able to compare it to a Halcyon 18watt HID light, and the difference was huge! the Halcyon's light had a bluish green tone where as mine had a really bright, pure white color to it, also the lens it came with (comes with spot lens and interchangeable to flood or video) produced a large hot spot with a good size halo to go with it. It was abit too bright for the fish, it kinda scared/pissed them off so I had to avoid pointing the hot spot at them. That was the only down side along with the fact that divers with less powerfull lights were significantly overpowered and makes it difficult to see them at times. I often had to "muffle" my light to see them. So I think I'll get the 10Watt HID specifically for night dives(Which is the beauty of this system).