OnePsychLynne, no matter which you pick someone will tell you you need to change it right away to make it better.

M&P 9c was my first auto and despite what I've read I find the trigger just fine. No need to buy Apex parts, though I'm sure they make a fine product. I just put many K rounds down range and learned the trigger and sights.

I have fired the PX4 subcompact and thought it was fun to shoot but didn't feel quite right in my hand. Don't know anything else about it.

Good luck in your choice.

Dave