Dale-
If you have successfully cooked BB's, then you will be just fine with spares. They take longer (depending on how much you trim), but other than that, they are a pretty similar cook. Membrane, rib, smoke, foil (if that's your thing), test 'em for doneness, eat 'em. No worries!
I have been using the CostCo ribs for a while now, and they are my favorite for sure. In my area, they are Swift brand, and they are consistently good meat. Good luck, and check back and let us know how it goes!
Rich G.