Overall the best dedicated slug out there is the Savage 220f, behind that is the H&R, I have both. I see you mentioned the Remington 870 and 1187, both well proven shotguns I do have the 1187 in both 12ga and 20ga., they shoot very well. If you considering the 870, don't discredit the Mossberg 500 combo, on sale at Dick's Sporting Goods this week for $309. You get two barrels, one is a field barrel with a few chokes the other is a rifled/cantilever barrel that has a useless scope, just upgrade it. I love the 20ga, I hardly use the 12ga. When speaking ammo for the 20ga. I like 3" sabot slugs, the 12ga I like the 2-3/4". Here is a picture of both of my Remington 1187, both are for sabot slugs only, both topped off with a Leupold VX-II 3-9x40 using 3" Remington Accutip, and both with a Monte Carlo stock