Mechanical keyboards as you've linked to one such peripheral are a personal preference. There's no best especially after there are multiple variants of switches, designs, functionality and ofc price points. If one person says X is best, another will come and say Y is best or better. This is a subjective topic, IMHO. An argument can also be made to build a custom keyboard for gaming and every other task that you plan to do under the sun. In fact there's also a point to be made to have a smaller form factor keyboard like a 60% and have your hands/wrist at a natural angle when playing FPS games.
I've also gotten into custom keyboards to a small degree and one other thing I've noticed is keyboards marketed as gaming peripherals are either hit or miss...just steer clear of anything with a Razer logo on it.