But G29SFWTF, those 10mm rounds are hot enough that standard overpenetration is something to be concerned about. I honestly can't figure why a guy would want to INCREASE the chance his round will pass through by using FMJ bullets.
I work with and around lots of bad guys for a living. I'm an Active Shooter Response Instructor for my agency and I've spent years dealing with parolees and gang bangers. The LAST thing I'm worried about is them having soft body armor. If one-in-a-million chance they are wearing it? Punch em with your 10mm rounds and then work in a head shot. My professional opinion, as someone who's seen a LOT of shootings and is married to a judge, is to stay away from staggering rounds. That kind of horseplay will hang you in court and more importantly, could injure someone you don't want to hurt.
"You find it offensive? Well I find it funny. That's why I'm happier than you."