With modern ammo, I don’t feel under-gunned with 9mm, though my main carry is .357mag. BTW, what are your thoughts on your MK9, I have the PM9. It has not been reliable enough to trust my life with it.
It's heavy and considering that all I wear is sweatpants with draw strings rather than jeans and a belt (I'm retired and don't have to dress normal anymore)I have several holsters for it and none of them will accommodate me. The last time I tried to carry it, the holster and gun fell off my pants when I stepped out of my car. The only solution for me is to purchase a carry vest........
As for firing the gun itself, I like the heavy weight which improves it's accuracy and I've never had a jam.