Well, having both the Blackwidow and the g80-3000, one clear QC difference is that all the caps on the g80-3000 fit the same. The stems seem to be uniform on it, whereas on the blackwidow keys would randomly come off quite easily (if you wanted to remove them) or be extremely hard to remove.
I thought pbt is much harder to work with, due to shrinking, but razer's OEM doesn't seem to be able to get it right even with ABS.
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