IIRC, making armor is not an easy task. It requieres a technology not available to all because of cost. So there are just a few true armor manufaturers, and a lot of resellers. Am I right? In that case, how do you know which is a manufacturer and which a reseller? Because I guess that question could explain different price and performance.
Is there any list of armor manufacturers and resellers with their products and features? That would be interesting information to compare armor.
By the way, what about the Norwegian NFM Group, are they armor manufacturers or just resellers? how their armor compares to others? Asking just because here is an easy choice due to being European (import from USA is difficult and expensive).