Try flying a helicopter on GTA4 with the realistic handling mod, not happening.
Yes ofcourse keyboard and mouse is better for fps/rpg etc, and i can even drive nicely on gta4 - drifts and all. But you get in a helicopter (which i incidentally love to fly) and it's ridiculous.
The controls are: W = power up. S = power down. A=Turn nose to left, D= Turn Nose to right. numpad 4 = bank left, numpad 6 = bank right. numpad 8 = nose forward, numpad 5= pull back. You should try it useing them controlers, it's very hard - with the handling mod. It's not to bad without it.
I gave up getting it to work and am just going to order the Xbox 360 controller for windows.
However, i did get it to work on my desktop
which is fun.