Welcome to the forum. Other, wiser heads will answer your questions about the .32-20, as I have little experience with it.
But to clear up one question. The pistol is called the M&P (for military and police) as it has fixed sights rather than target sights. The name "M&P" or "Military & Police" was never stamped on the gun.
The great disadvantage to the fixed-sight pistols is that you can't easily adjust the sights.
The great advantage to the fixed-sight pistols is that you can't easily adjust the sights.
(You don't get something for nothing).

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and what his trumpet saith