A few years ago I bought a used Mossberg 500C in 20 gauge for $155 out the door at a local gun shop. Now they're having another sale, and I can pick up a used Mossberg 500 in 12 gauge: wood furniture, 18.5" barrel, gold bead front sight, 6-shot magazine. Condition looks to be very good. Price? $135 plus tax. I would likely add an AO front nightsight, and perhaps replace the hard plastic recoil pad with a rubber one. It would be used for HD and, if I ever bird hunt, I'd throw another barrel on it. So, is it worth it? Or am I just wasting my money considering I already have the 20-gauge set-up the way I like it?