I prefer the Aimpoint, but both are rugged. Here is why:
Some people say the 65MOA circle helps more for close in work. The Aimpoint circle created by the body of the Aimpoint can be used the same. For those distances, my recticle never leaves the eye anyways. Wherever I look, the weapon is aimed and ready to rock.
Its all in how you train. When ever I go into a small place with lots of places for bad guys to hide, weapon is aimed everywhere I am looking.
I also prefer the closed tube design of the Aimpoint. It seems less likely to break or have an obstructive view.
I am not to big on plastic optics. It seems rugged and I have no reason to think otherwise, but come on..... it's plastic.
Finally, the 4moa is perfect to me. Small enough to engage targets out to 400M and large enough for close quarters.