I just got my Surefire x300 ultra from Bot.ach this afternoon. And man is this sucker bright! I dont even know how to explain how bright it is...Honestly, it may ALMOST be too bright for clearing rooms indoors, but outdoors, you could easily make out people from a hundred or more yards away, it is ridiculous! I bought it for my Spike's Tactical M4, and for ten extra bucks it came with a mount that mounts to the front sight so that the light is sitting at 12 o'clock. It isnt too inconvenient to reach up and turn it on, but obviously a remote switch would be much better! For as much as surefire charges, remote switches should be thrown in...naturally you have to buy a new battery door as well. All in all, to get it set up for remote switch capabilities, it would cost more than the light cost initially. Bo.tach has an excellent price on them right now, IMO, $209 for the light, and $220 for the light plus front sight mount, and as usual free shipping. But, before you order, call and make sure they are in stock, I always do this, and it always makes for a trouble-free order. However, if you are backordering with them, I'll be praying for you... Anyway, Im sure you are all already aware of the high quality surefire is known for, and they did not disappoint this time. I dont know how they measure lumens exactly, but it does seem to be a legitimate 500 lumens based on what Ive seen from other 150 & 200 lumen lights.