I've got one of the 2.7-4.2V 3-mode 1.5A models in a solarforce L2 host. It seems brighter than any of my other high-output lights (T20C2 MKII, M20 R5, JET-III M) on high, but its not a thrower - the others definitely out-throw it. Instead it has a wide hotspot with a smooth transition to a bright spill, very good for area illumination - its the one I keep in the cabinet for when the lights go out because of the sheer amount of light it emits. Also the low mode is lower than any of the others mentioned above as well. I measured the tailcap current a while back, I can't recall exactly what the numbers were for medium and low, but high mode was ~1.6A on a fresh-charged 18650 . I've been really pleased with it. It fit the L2 fine with the spring that came with it, I tried it in a Romisen RC-M4 and the supplied spring was a bit to narrow - I had to use the Romisen spring to get proper fit. I don't have any Surefire hosts to try it in. Hope this helps!