I've been in on this question a few times before and have weighed in with some enthusiasm. Instead of replicating that, let me simply pose a question.
If you were asked to make a choice; which knife would you choose to keep in your pocket for self defense?
This...
Or This...?
Well... that's simple as Heck, Right? Obviously the one you can operate with one hand quickly. I don't want to worry about grabbing it with my right hand, using my left thumbnail to dig out the blade, and change my grip before I'm ready to use it, ESPECIALLY if I'm being attacked in the meantime.
Think about it.
~LT
PS- G19 (17+1) ALWAYS, or M&P9 (17+1) ALWAYS.