Currently i have the Seraph P7 M Turbohead from lumens factory, it claims 950 lumens but only puts off about 500, the throw is nice but there is some spill, its also heavy (well heavy enough to be uncomfortable on the end of an AR), i had it on my M961XM07, but with only 2700mah usin (3) 900mah rcr123s i only got like 14min on full blast. I use that P7 head on my Seraph SP-9 and it rocks with a couple 18500s. As soon as my card is verified on paypal im gonna pick up an D36 XM-L assembly from nailbender though you do have to open your SF head (i boiled mine it was super easy) it will save you some money and weight. im thinking of just boring out my 6P and using an M adapter cause it would give me more power and still be lighter than my M961 setup