I have both. As the Shield is not on my employer's authorized list, I don't carry it. The two main differences are width and weight. The 9c is basically a chopped down double stack pistol, so it holds more rounds, and of course, is heavier. The 9c is not bad on he hip, but I find it a bit heavy on the ankle. Also, I don't think it carries that comfortably in an AIWB (maybe cause I haven't found the right holster. The Shield, because it's lighter and thinner, carries well in an ankle or AIWB. Both are combat accurate out to 25 yards. I haven't spent that much time with my Shield on the range, but know that I can hit with it. I prefer the seven-round mags for carry for the Shield. It's a concealment pistol. I use both the flat and extended base plate mags for the 9c. I shot a baby Glock with standard mag base plate for so long it doesn't bother me if my pinky curls under. Having both the 9c and Shield is not a bad idea. What you carry will depend on what you're doing and how you're going to carry the gun.