My circa 1987 12 ga. 870 "Special Purpose Deer" model started life as a smoothbore slug gun with rifle sights, (back before rifled slug guns became common). Got drilled and tapped for a scope in the early 90's and added a fully rifled Remington barrel back around 2001. Always seemed to prefer 2 & 3/4" Winchester BRI sabot slugs, although there were some other good ones, I finally standardized on the Winchester/ BRI's. In 2013 I purchased over 350 of 'em so at age 66 (this year) I figure that's probably a lifetime supply for me, as I also rifle and handgun hunt so it's not as if I need that many slugs annually. One thing I've noticed over the years is that even back in the smoothbore foster style slug days or the fully rifled barrels and sabots of today is that both of those remington made barrels preferred Winchester slugs. Probably not all Remington slug barrels are like this but that's my experience with the two that I have. P.S. Back in the smoothbore days I went through the 3" magnum slug phase and eventually went back to the 2 & 3/4" stuff when I realized that the deer couldn't tell which one I was using but the 2 & 3/4" slugs were more accurate, so I've stuck with them ever since. So whatever is most accurate is what should get chosen.