well, it depends
Right now, the ready shotgun is a vintage defender with a surefire light on it, but that's the one usually set aside for my dad (him being one of them deformed right handed people) dad took my ready shotgun to vegas with him to test stages with.
since i'm left handed, dad bought me a mossberg 500 for graduation, and i put GR sights on it (had to modify the front ramp so i could screw it on instead of soldering) an i voted sticker on the left side of the reciever, a butt cuff(suitably reversed for left handed people) and a chunk of mousepad material under the comb to correct for stock drop.
there wasn't a setting to vote for both, so i voted for the one i use.