A lack of analog controls is definitely an issue. Having digital buttons on keys that are either 100% on or off loses a ton of fine control.

Playing GTA and need to make a slight left while driving? On a gamepad you just slightly tilt the stick left to make a smooth turn. On keyboard you have to do a bunch of short little taps on A (and D when you inevitably oversteer) to stop yourself from jerking the wheel left.

I remember really wanting a Logitech G13 when they came out but I could never justify spending the money on one.

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