I have the Nemesis. They are OK as far as maintaining position and releasing the pistol but they do print in tighter pants.
You can avoid this with something stiffer and wider like a piece of leather or the like. Just place it to the outside to break up the print.
I had never heard of KNJ holsters till this post and a bit or googling. I can't directly answer your question, but I own 4 Nemesis holsters - one each for all my pocketable guns. The ones I have used for more than a few days have broken in and have formed themselves well to my pants and leg. They do not print in any noticable way.
KNJ Pocket Holsters won't cost you a bundle. I paid <$15 for mine. KNJ LLC, Gilbert AZ makes two sizes of pocket holster that are VERY close in size. They are rectangular, with a pocket on both sides, and therefore ambidextrous. Most people use the outside pocket for the pistol. I use the inside pocket, as that puts more material between the gun and the outside of my pocket, which reduces printing. The only real reason I use one is that it will accept a PF-9 or P-11 with the ArmaLaser attached. http://www.ccwsupply.biz/KNJPocketHolsterPAGE.htm
Gun holster is sewn on BOTH sides of the pocket holster so you can use left or right, OR, pack a spare mag, cash or ID in the other side of the pocket holster.