Vortex Impact 4000 is good for most situations. It's chunky AF and works as advertised, but the display is LCD so it can be a fail point in very cold weather and is too bright in dark night conditions even on the lowest setting.
MARS-mc is smaller and lighter, has a much better display that wont crap out in the cold and is totally useable in the darkest of night. The surface of the display is pretty smooth so there are edge cases where it can be hard to read on a sunny day if the angle of incidence is just right (I just shield the display briefly in those cases). I also think the MARS-xx is overall easier to use in general with a much better interface and workflow, but that's subjective so YMMV.
MARS-mc is 980nm and MARS-c & lc are 1550nm - and neither has issues ranging past a mile, from my experience. The only thing that really disappointed me is the MARS-c illuminator/pointer -
it feels anemic compared to similar civ-class LAMs. The interface and way you dial beam divergence is really nice, but run next to a MAWL-C1+ or a RAIDXe civ, the MARS-c LAM just isn't as strong as you would expect.
