I found some pretty nice wheel settings for G25/27...
Profiler Settings...
Overall Effects Strength = 104%
Spring/Damper Effect = 0%
Centre Spring = Off & 0%
Degrees of Rotation = 350
Game Settings...
Advanced Wheel Settings...
Steering Deadzone = 0%
Steering Saturation = 35%
Steering Linearity = 20%
Throttle Deadzone = 0%
Throttle Saturation 10%
Brake Deadzone = 0%
Brake Saturation = 10%
Force Feedback Options...
Environmental Effects = 20%
Feedback Strength = 100%
Wheel Weight = 30%
This setup feels great to me, even though you dont actually use all the 350 degrees rotation (think the lock is 220 or something) it allows the onscreen wheel to turn the same rotation as the wheel you are holding (shame you cant switch the on screen wheel off!), but still feels silky smooth