Fmjs = full metal jacket rounds, or "the cheap stuff Walmart sells".
Fmj is much cheaper to shoot than hollow point rounds.
The 100 round "value pack" of Winchester ammo that Walmart sells is all I shoot in this gun besides some occasional carry rounds.
The PM9 loves that ammo!
Eats it all day long, and is very accurate with it.
The jhp that I carry in the gun, Speer Gold Dot, 124 gr. +P is a hot round.
Though I got these at a price that was almost as cheap as fmj rounds, I don't think a steady diet of +P ammo would be good for any gun.
And I guess the other part of "Why so many FMJ's?"
is that I like to shoot, and the PM9 is fun to shoot.
Mine was $550 before tax, and it may be the most expensive handgun that I have ever bought.
I won't pay that much for a gun unless I am going to spend a lot of time with it. Carrying and shooting.
And, it needs to work.
This one does.