I used to have a SA XD 45 ACP and a Ruger SP-101 DAO. Two totally different guns. I figured one would be primary and one would be backup. But that didn't work out too well. Two totally different guns to shoot. Different ammo to buy. Not to mention two guns to clean after shooting at the range. I sold both of those. I now have a SW MP 40c. I think I will like it. It will be my primary. However if I was going to have a backup, guess what? It would be the exact same gun. Why have two different shooting types? Why not have my back up the same as my primary. My hand and mind wouldn't know the difference and I would shoot both the exact same. Not a second wasted to recalibrate my brain in the heat of battle. Anyway I would like to hear people's thoughts on this. Are you with me OR would you say that it doesn't have to be that strict?