I can game on rubber domes, but that doesn't mean I prefer it that way.
The thing I like about mechanical keyswitches is that I can feel exactly when a key actuated and released without having to rely on feedback from the game itself. It gives me confidence that the input device is doing exactly what I want it to do. Yes, this means I strongly dislike linear switches, even for FPS gaming. For me, the ideal is the IBM buckling spring or Cherry MX Clear.
I'm currently on a Cherry MX Blue-based board, partially due to the general lack of Clear-based boards, but also to familiarize myself more greatly with such boards in general. The higher release point is far from ideal, but I have to have that tactility, and it's not as much of a problem when I have a habit of releasing keys entirely before depressing them again. I don't like Browns because they're too close to linear, which leaves the much rarer Clears.