This is a great thread. Brings back lots of good memories of classics. I will add mine:
Winchester Model 12. Great gun and still my favorite upland piece. It just comes up so perfectly. I like other pumps, Wingmasters, BPS's, the Rem 31, but there is just a mystique about the Mod 12. It will never be made again but they are not hard to find in pretty much any flavor, except 28 gauge (wish I had one!)
Benelli Super 90. I still like these better than the M2's. I think the cryogenic barrels are great on the M2 but you can keep the comfortech stocks.
10/22 Magnum. I still don't know why these got canned. A simple (better) extractor fixed mine and it has run flawless since. These would sell like hotcakes if they hit the market again.
Winchester Model 62. These were fun to shoot and the ones I have shot are super accurate and great plinkers.