I've seen this photo online for years, and I just wonder how legit it really is. Everything seems okay until you look at the mushroom-cloud fireball at around 7" into the 10mm track. This needs vetting or at least accompanying data not represented here IMHO.
"pocket?" probably a .357 revolver, or a .40 auto if you don't want to go the 10mm route. Do whatever you want though, there's tons of suggestions in this thread already.
I agree, I would like to see or even do some ballistic gel tests myself, but it just looks so freakin' cool, I can't resist throwin' it out there every time somebody mentions the 10mm.
I have a Glock 20SF and will soon be getting a 29SF for EDC, and I can honestly say, that even if that graphic is exaggerated, I love the 10mm round for it's sheer power and versatility!
Those that have never shot a 10mm, just don't know what they are missing out on.