Been out of town for a few days, so I'm late to the party.
In any event, let's see:
Winchester Model 12 - 12ga
Winchester Model 12 - 16ga
Winchester Model 42 - .410 varient of the Model 12
Winchester 1300 Defender - 12ga
I've also got a couple of Benelli's, one in 12ga, the other in 20ga.
After that, there's not any duplication.
Out of the dozen shotguns around here, I've got models from 6 different manufacturers, in 4 different gauges (12, 16, 20 and .410), and a variety of action types (O/U, pump, gas-auto, recoil-auto... even bolt).
Part of me just likes the variety. After shooting a ton of clay targets over the past few months (using a Browning O/U), I finally went out and shot a round of sporting clays with the Model 42 last week. I broke exactly 70%, but had a big grin the entire time. Now that I'm done with winter trap league, I may try my hand at 16 yard .410 trap this week.
I guess I like guns in general and enjoy different designs. I just prefer the Model 12s a bit more.
Probably because that's what dad shot. 'Course he also shot a POS rusted-out Sears 12ga bolt gun as well, but we won't talk about that.