Porting makes a "huge" difference, indeed. It dramatically increases muzzle blast and directs it straight upwards, potentially at the shooter.
Nonsense, I have never encountered this problem. I love them.
Compare a loaded full-size pistol of your choice, and the loaded Five-seveN will be dramatically lighter.
Compare a Glock compact of any kind and it will be dramatically shorter.
The LAPD is virtually alone in their choice of that specific sidearm, so by your own logic it is not a preferable choice of sidearm.
Actually no, there is no one choice, there are many choices - which is what I've been getting into you this entire time.
While Glock is majority (and for many good reasons) there are several viable options and no gun is best, I don't prefer Fiveseven, and most don't, but if you like it, well, good on you.