I'm not-- decidedly not -- a concealed carrier. For me, that's like carrying a running chainsaw around. I live in a low crime area and ISIS activity in Northern Virginia is at historic lows. I have no input on holsters.
But, I think the P320 (upon which the m17 is derived) is a fine pistol and have been shooting it since the first year it came out. SigSauer has been excellent in supporting their product. As a reloader I had some early production rounds I finally decided to shoot -- during the craziest ammo shortages during Covid -- that were overloaded w/powder. Damn near lost my face and hand when it blew. So, I called SigSauer to get the repair parts and was asked to be honest about what I did and I said...yes, this was my fault. The support guy said...ok, they would fix for free. I was amazed.
Were I interested, the SigSauer P365 seems to be a very nice concealed carry option. I own the P232 which is the SigSauer that looks like the Walther PPK and for a 9mm option i have the Walther PPS2 but again...I'm not a concealed carry person. These smaller guns are snappy and not near as interesting to fire as the bigger framed M17/P320. But, I have shot the P365 and it is much easier to control than the other two concealed carry guns I have so if I were to decided to concealed carry again, i would look at that.