Ok sorry, I pretty much meant, linearity (probably the most important), resolution (second most important) and the backlash I would imagine is linked to resolution? All I'm doing is making an improved version of a joystick with better characteristics. My joystick which is a Microsoft Sidewinder 3D Pro is pretty good when it comes to the throttle lever but it could improve slightly in my mind. I think I'm looking for a bit more precision. But certainly, linearity is a very big issue here also - not totally important but for what I intend to do, it's definite bonus making the end result much simpler to implement.