I have or had several of the guns mentioned. I like the LC9 for one reason, It can be pocket carried.The others can be forced into that role but not without compromise. I had an lcp, but after 2 years I woke up and decided my old philosophy of "why carry a 380, if you can fit a 9mm" in the same place. I tried the shield, nano, sig, and my 26. They are all too big bulky or thick. the LC9 may not be the finest weapon out there but it does fire every time and it is accurate at 25 feet. With the laser that came on mine it fits in any of my pants front pocket with a "sticky" holster. These holsters are the best thing since sliced bread, inexpensive enough to get one for every carry gun, and the stay where you put them, "thus the sticky" I can move holster and gun to mid waist when driving, and there it stays until I re-pocket it.
I almost got the shield, it's a nicer gun, but 3 of us in the store all agreed it's too darn big to pocket carry, and if I wanted another iwb, I would get another type of steel gun. Or just use my Glock 26 or 30. Most of us have a half dozen of these small 9mm to 45 caliber mini guns as it is. The LC9 will pocket carry best, and will fire every time I have pulled the sloppy trigger,so it works for that.
Also I just sent for a pair of these "CCW Breakaway" pants in the cargo style. They have 2 holsters built into the pockets, that are adjustable vertically and laterally. They will fit a fullsize 1911, to a 380 lcp. Nice folks he was an engineer. I have read good things about them, they make a cargo, a dress kackie, and jeans in blue denim. Also they make all the same in shorts. So for about $100.00 plus the little nylon extra piece I ordered to go between the holster and inside pant leg, you have a nice pair of pants with 2 holsters, one for your gun and one for your mags. The extra cargo pocket can take your wallet keys glasses etc, So google them and I'll let you know when I get mine.