Quality control definitely lacking - Primary Weapons Systems EBT Mod 2 End Plate and Castle Nut

I purchased three of these a few years ago, and they seemed to work fine under minimal use. However, I purchased four within the last month and they are definitely lacking in quality control when compared to those first three. The end plate key/tab doesn't properly engage the channel of a mil-spec tube that has been double checked for proper dimensions--it will free spin as the inside diameter of the end plate is just too large and the tab is too small. Also, the "ratchet" pin in the end plate that is designed to engage the serrations/groves on the outside diameter of the castle nut do not even come close to engaging when installed. There is a 1/32" air gap and no way for the product to work as designed and marketed. I have a picture, but there is no way to display it here. I'm frustrated and now waiting on traditional mil-spec hardware. Having lost all faith in this product, I am returning all four recent purchases and replacing my original three. I like the concept, but the latest implementation just doesn't live up to the expectations.