I despise playing any game with a keyboard and mouse. First of all, I have carpel tunnel on my right hand, which makes using the mouse for long periods of time or performing repetitive movements makes my hand very uncomfortable. Second of all, there are NO ERGONOMICS. You have a grid-divided button layout keyboard and a mouse with 2 buttons that make an annoying click sound. To move around, people usually choose 'asde' for up/down/letf/right etc. It just has no feel to it. You are literally just pressing rectangular buttons to control your character. I'd rather use something which yeilds a more realistic and depthening feeling such as a joystick. Also, the mouse has no feel compared to a joystick. Joysticks easily require more skill to those used to a mouse, and vice versa, but joysticks offer a more natural feel. There are limits to your movement as well with controllers, which gives you a more natural and solid feel when moving, strafing, and aiming in different directions.