Weird I have had two G25s over a 3 or so year period, and a friend of mine had one as well. With wheel pointed completely straight I had no FFB. Even in RFactor 1 with the FFB set to full to get the wheel vibrations simulating engine rev vibrations It would only kick in once I moved my wheel a few degrees left or right. Also, you may not feel anything in your real life wheel when its centred, but im sure you still feel bumps, rattles, g forces, locked brakes through your body and the car etc when your wheel is straight . Sims arent 100% just translation of wheel forces, if they were then we wouldnt be able to drive these sims the way we do. 75% or more of real life car feeling does not come from the wheel, but the g forces, shakes, seat of the pants etc. Many of these forces are simulated through FFB in our sims in order to make up for all the forces we would feel in real life elsewhere not through the wheel. So we need forces in the centre, even if a real life car doesnt have much forces/feel through its actual steering wheel when centred.