Out of the box, most of your quality brands (Sig, H&K, S&W, etc.) are going to be on par with each other. H&K claims their USP pistols are the most accurate out of the box, but it's been found debatable. If you're just looking for a basic self defence handgun, the differences will likely be negligible. If you're looking for an actual target pistol, and are going to shoot expensive target loads through it, the Sig P210 is - if not the absolute best choice - among the best choices.
For the AVERAGE 9mm pistol, not very well. The M9 pistol is considered to have an effective range of 50 meters. There ARE 9mm pistols and shooters that are accurate to 100 yards- but not an everyday affair.
Most likely a 9mm with a suppressor
probably If the pistol is designed for 9mm Luger, 9mm Para, or 9x19, yes.
a 9mm is not very powerful and i have one and a can shoot it and hit the target at maybe 150 to 200 feet if you want to be accurate at all
9mm pistol
50 meters for most.
The 9mm pistol would have the higher decibel rating.
Both can be equally accurate
No
H&K claims their pistols to be the most accurate out of the box. This has been disputed.
A Glock 19 is chambered in 9mm. 9mm is one of the most common/popular pistol rounds.
9mm MKV is not the same as 9mm Luger.