The problem is that the logitech g25 has two motors in it.
On a normal wheels like the momo it only has one, therefor when the wheel is at center the one motor can't keep the wheel at center properly since the motor only has the ability to push to either direction and not "locking"
In the case of the g25 since it has to motors, it can lock in the middle, just pushing those motors towards eachother.
The problem with lfs is that it doesn't support that.
Instead it creates a zone near the middle usualt within a certain % of the exact middle where it doesn't apply any force at all.
If lfs could be configured to remove that gap when using a g25 this problem would be out of the world.