For a rifle mounted light I use a Fenix PD35 in a Wyoming Arms mount. And it's what I'd choose again, without hesitation. They run $150.
http://wyomingarms.com/product-category/light-body-accessories/To save a few dollars less I'd get the Streamlight Pro-Tac Rail Mount 2. It comes with a mount, or they use any Surefire Scout mount and come with a clicky tailcap and a tape switch with momentary and constant buttons. I played with one last weekend and was very impressed. They're gonna put the hurt on the Scout series.
I shot a night match with it last weekend and couldn't have asked for more from a rifle light.
Again, for a handheld light I'd do a Fenix PD35.
You can get rechargeable batteries for the Fenix light and they have adjustable brightness to conserve juice.
Here's a review I did of the light that includes a video comparing the PD35 to several other models.
https://www.24hourcampfire.com/ubbth...58943/all/Wyoming_Arms_High_Lumen_Light_