Funny you started this thread because I did some tests today with my carry ammo. I carry some home brewed 124 gr. Golden Sabers in my Kahr CW9. I was firing into water soaked phonebooks, as some say is comparable to a human body.
Anyway, recoil is manageable and penetration was roughly 2.5 phone books...that was on par on with the 165 grain Gold dots out of my Glock 27 i noticed. After seeing the damage and the mushroom of the Golden Saber, I'm a believer in 124 grain bullets. I'll try and post a picture later.
edit: It is worth mentioning that what Chris said is pretty much what I've read. From my readings and from all of the tests I ran today with various calibers, I've come to a broader conclusion: As long as you have decent JHP ammo of any brand, then shot placement will pretty much be the deciding factor
He’s the fellow to please-never mind all the rest,
For he’s with you clear to the end.
And you’ve passed your most dangerous, difficult test
If the man in the glass is your friend.