For years in the military all I was allowed to carry were FMJ's. I now tend to carry the heaviest hps i can with back up mags loaded with fmj. I don't worry about over penetration in the least in 45acp. In 44 I like 240 jsp with speed-loaders in hard cast. If I need a reload I'm guessing I will need penetration through some kind of concealment.
Penetration is the most important factor to me in selecting a defensive caliber. People in general have a poor understanding of physics and ballistics and have wildly unrealistic ideas of what a particular round is going to do.