I don't know of any problematic years for PM9's especially as late as your looking at.
I personally love the Big Dot sights, they work very well for me. I have them on my PM45.
Have the standard dot on a 1911. I'll probably go Big Dot on everything eventually.
In Memory of Paul "Dietrich" Stines.
Dad: Say something nice to your cousin Shirley
Dietrich: For a fat girl you sure don't sweat much.
Cue sound of Head slap.
RIP Muggsy & TMan
"If you are a warrior legally authorized to carry a weapon and you step outside without that weapon, then you become a sheep, pretending that JOCKO will not come today."