Pentagon makes some good ones as well, I've had a couple of them for a while now. They survived multiple deployments overseas and field ops here. I'd recommend going LED with what ever you decide, the other likes to eat batteries.
If you are using a forward grip you can mount the light off the side of the weapon and use your thumb to activate the pressure switch on the back of the light. Remember the barrel sight (the brightest spot of the light projection) relationship will be off the distance of what ever mount you use.