From my point of view, it has more to do with options for customizability and case shape. I have owned razer keyboards in the past, and have not had any QC issues. Mind you, that is a small sample size; but I have heard other people have inconsistencies with switches and poor keycap legend quality. In terms of "GAMING PERFORMANCE!" I have not noticed a different in key actuation between razer and the custom key switches I have used. It was not perceptible at all, in terms of latency. Finally, if you are on these forums, you are generally looking for a more bespoke experience, than just an off the shelf keyboard
Keyboard enthusiast are a bit of a different breed, and generally are looking for something unique. So take that with a grain of salt.
Hope that helps.
Cheers,
Chris