If it's alright with you ZeKer, I'll answer your question about shotguns.
Most of my fellow shooters like the Red-Dot sights for the shotguns they use for home defense.
Those optics are best used with a pistol-grip stock, though I would imagine standard stocks work fine, but "tactical" is all the rage right now where I live.
http://www.tacticalshotgunaccessorie...rs/default.htm