I have the Corsair. It has terrible key caps. They break frequently. The HyperX is much better and robust (I bought it after I was disappointed with the Corsair).
Logitech G513 is the way to go. Cleanest looking keyboard out there. Plus new Romer G linear switches not only feels great but perform better than any of the Cherry MX's. My opinion.
But rgb on keyboards is one of the only (if not the only) things it makes sense on... Also gaming keyboards are usually cheaper than high end typist/enthusiast Keyboards. Also, the rgb on the keyboards doesn't really add all that much to the cost of the keyboard.
It's usually about 5-10 dollars more than the standard version on lower end keyboards and 15-20 on higher end ones.