I'm sure it's a dumb question but, hey, I'm a revolver guy. Moonclips are high tech for me. When I bought this XCR I got 10 extra 30rd mags, five alloy and five Pmags. Gotta say, it seems like a lot to me. Plus, looks like mags ought to last forever, and you can rebuild them, I think. Reading various posts, though, it sounds like some guys buy mags by the truckload and store them in small warehouses. Maybe I ought to buy some more. How many are really necessary, I wonder?