I am inexperienced with holsters & have ordered a few & picked up a few at the LGS.
One of the first I bought was the DeSanti Superfly mentioned early on that I got at Steven R Jenkins Co at 6680 East 21st St that caters to LEO.
I have used it with my J frame revolvers & small 9mms.
I have gotten decent holsters with used guns I've bought.
I've had good luck with the inexpensive Sticky holsters for being able to tuck in your shirt.
But, what I don't understand with IWB holsters is that when you get one specifically designed for your gun, it might or might not have a "backing" covering the end of the slide so it doesn't dig into your flesh.
And, none of the ones I've tried or seen, have a "backing" extending behind the grip, so that digs into you.
I've actually seen a "backing" you can buy to put between your skin & the gun's grip & slide that digs into you, but at $20 I haven't bought one yet.
A hybrid holster with a leather backing and a kydex shell that is molded to the particular gun. You can get them with or without a combat cut that cuts away the backer from the grip to allow you to get a full grip on the gun. Amazingly comfortable way to carry with a good belt. Typically slide it back further than the 3 o'clock position, just depends on preference as to how far.