I recently got to examine one of the US Army's newer scopes for the M16. It has a lever for instant switch from 1.5x to 4x magnification. It has a switchable red dot or crosshair reticule. Had nice eye relief and apparently good optics. Supposedly rugged as can be and waterproof. A little bit heavy at 660 grams. The reticule is visible even when the battery is dead. Probably be seeing something like this in civilian colors before too long. Probably pretty costly though.

Very expensive, heavy and poor optics for the price.