I'm kinda confused as well about the "complicated" part of using a MRDS. You put your cheek on the stock and voila, there's a red dot in front of you. Sighting in may be a bit complicated since there's fiddly little screws to turn, but anyone dextrous enough to use anything more complicated than a single-shot should be able to manage without taking any night school courses.
My 930SPX wears a MRDS on its rail, with the red dot sitting just barely above the fiber-optic. As the red dot isn't quite as bright as the fiber, it gets washed out in the daytime, but in darkness when the fiber is useless the red dot is quite visible.
Sure, it needs batteries ... about every five years. I'm pretty sure at some time in the interim I'll have changed batteries and resighted as necessary. If I forget? Meh, that's what the irons are for.