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The only real problem I have with Full Metal Jacket ammo (aka FMJ) is that it has enough energy to completely pass through a human body. Jacketed hollow point ammo (aka JHP) is designed to expand inside the body, thereby helping prevent the bullet from passing completely through the body as well as enlarging the permanent wound channel (the real damage to the shootee) to help increase the speed with which the shootee stops doing whatever it was that made the shooter shoot in the first place.

Personally, I carry Hydrashok HST JHP ammo in my .45 ACP pistols. I figure that since it feeds reliably and has advantages over JHP, and that since it will never be smaller than .45, the potential advantages make it worthwhile.

My father is a Korean War-era Marine, and he carries FMJ in everything. He says he wants to be sure that it will function and that a .45" hole is big enough if you shoot them 'til the magazine is empty.

Almost forgot...
FMJ ammo doesn't usually fragment at pistol speeds (rifles are a different ballgame). JHP ammo sometimes does (you'll find there is a lot of "sometimes does" with JHP) come apart, but I don't know that I would worry too much about that. In the case of flying ashtrays (JHP in .45 ACP), having it break up a bit just means more wound channels and more damage. If I'm shooting someone and the round breaks up some, that mostly means they will hopefully stop more quickly.