I do love the PX4. Since I got this as my first sidearm I have shot a few other guns, but this is by far my favorite so far.
I am thinking about getting a compact for when I naturalize (then I can get my concealed carry) and I held a whole bunch of guns, and the ones that stuck out to me were the Springfield XD Compact and the Smith & Wesson M&P Compact, both in 9mm. I think I am going to buy the S&W since it is completely ambidextrous. Being a leftie can sometimes be a bit cumbersome, especially with the slide lock.
As far as deadness goes, I wonder how I'll do in a pressured situation. There's only one way to find out: take some combat courses and compete. Getting my heart rate up there and then trying to shoot will prove if I will survive or not.