The gearing preference is really subjective. The MXC with close ratio lets you have exactly the right gear at any time, within a narrower range. The EXC gives you gears that will do everything, but you'll find yourself going slightly too high or too low a gear if you are highly sensitive to that.
Personally I find the motors have a wide enough power band that I can always find a happy place on my EXC. Pretty low 1st gear, plenty fast 6th gear. Common wisdom on this is a desert racer might like an MXC, woods riding with dramatic shifts in terrain calls for EXC. No regrets, myself.