A BSS is just about the best value going in a quality SxS, so it was a smart purchase. I have four of them (depending on how you count one that is a box of parts right now). I have used one of my 20s with steel for ducks, no problem. Converted one of my 12s to a two barrel set, 28" and 30". Converting the box of parts into a 20 ga 28" Sporter with a set of factory Sporter wood and trigger guard that I found. I like them a lot. The 12/28/M&F is a great gun for late season doves, especially in windy weather.
The drifting pin is easily fixed by applying a dab of blue Loctite and pushing it back in. If that does not work, you can lightly peen the shaft (or have a gunsmith do it).