Between a 40sw and a 10mm I'd say if you are capable of reloading, a 10mm would be the way to go. Because of its ability to load heavier bullets and your ability to measure your powder loads down or up with bullets ranging from 155grn to 200grn. Those Hornaday XTP bullets are quite well suited for hunting and self-defence. And lets face it. A 200grn bullet at 1000fps is going to beat out any energy a 40sw can deliver. Jim