I just got home from a match, where we shot shotguns with slugs along side our side-arms. The only similarities to actual defense was that you had to be behind cover and the adrenaline is going and effecting decisions. For ultimate reliability, I've always gone for the pumps. But when the adrenaline took over, there were a lot of hiccups, where people tried to pull the trigger without having racked the next round in, or they short stroked the pump. This was on a much higher number of the pump gun users than I would have expected. The guys with semis (Bennelis, Rem 11-87s, FN's and even a SPAS 12) cleaned house on the 5 targets, and quite speedily. The only hiccup in the autos, was one guy who was trying out low-recoil ammo in a Benelli M2. It was more of a FRONT SITE - PULL THE TRIGGER - FRONT SITE - PULL THE TRIGGER…. Semi-auto shotguns are more reliable than ever before. One of the things that favors the pump is that bird shot is never a problem with it, and that's probably usually all you'll really need in a home. Most semis will function with light loads, but some are finicky.