I did a great deal of testing on mine (PS3). I've found the preferred FFB menu settings really depend on if a) you want the FFB understeer dropout and b) if you aren't concerned about the wheel tearing itself apart.
The higher the Feedback Strength, the less the FFB understeer dropout is present. Around 50% it's all but disappeared without a dramatic shift in ultimate FFB strength (torque). The higher the Environmental Effects, the better the curb "bumps" are represented. But if you go off track, the amount of rattling coming from the wheel is a bit concerning.
I also played with Throttle Deadzone and Brake Saturation. Because of my seating position in my Obutto, I preferred a little throttle deadzone (~5-7%) to avoid "hanging" the throttle when I really wanted the throttle to be closed. It also helped me modulate the turbo cars a little better. I have a bad back, so a little brake saturation (~5-8%) helped decrease the force effort somewhat without affecting my modulation for trail braking.
My preferred:
Steering Deadzone 0% ( I don't buy the "a little bit of deadzone is recommended on high end wheels" argument)
Steering Saturation I think 10% (wheel set to 360 degrees, so whatever gets it to 330 degrees is what I use)
Steering Linearity 0% (I like a 1:1 steering ratio)
Throttle Deadzone 5-7%
Throttle Saturation 0%
Brake Deadzone 0%
Brake Saturation 5-8%
Feedback ON
Environmental Effects 70-80%
Feedback Strength 30% OR 100% (Depending on the car and situation)
Wheel Weight 0%
