I shoot 3 gun and have used california comp works and man mountain. I ended up switching to all man mountain 4 shell carriers. He's right, they aint cheap, but theres no plastic crap in them. they are also meant for the 2 3/4 shells right out of the box with a nice tight fit.Man Mountain makes the most popular but they aren't cheap.
Man Mountain Engineering Tactical Shotshell Ammo Carrier 12 Ga 4 Round