The difference between Cooler Masters Masterkeys Pro L and Pro S lies in the numpad, the Pro L has it and the Pro S is, as they say, tenkeyless.  Apart from that the boards are very similar, using your choice of Cherry MX RGB switches, Brown, Red, or Blues.  You do not need software to program the lighting or macros, they can be adjusted with the use of the Function key in concert with one of the F1-F12 keys but Cooler Master does also offer software which allows you to adjust your lighting.  The Tech Report liked these boards, finding them every bit as good as the major competition, with one notable exception; the prices of the MasterKeys are a bit lower which can make a big difference when you are purchasing a glowing, clicky keyboard.

"Cooler Master's MasterKeys Pro L and Pro S keyboards put Cherry MX RGB switches in no-nonsense chassis. They also expose most of their customization mojo through on-board shortcuts. We put our fingers to the keycaps to see how these boards perform."

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