This was a PRO upgrade
"Wow. Compared to my starter ruck vest, the curved and cutout plates do two MAJOR things. They take a significant amount of weight off of my traps/shoulders. Also, several miles into a hard ruck, they allow me to take a DEEP breath compared to flat weights. I cannot notice any shifting of the weights, and it holds snuggly to my upper body when walking. The "30lb" weights are actually 28. 4lbs because of the conversion to Lbs from Kgs. I wish they had heavier curved plates, but the vest is a worthy investment either way."