This has always been debated and I think it probably depends upon the year of your car and the climate conditions (corrosion). That being said I just installed Gordee's grownding wire set (10 wires). Without a doubt the mod I should have started with ! I have an 03.5 and it was like night and day especially with shifting in the AT. No hesitation anymore, the engine runs smoother than when I first bought it and maunalmatic mode shift instantaneously. I suspect that the 06's have better grounding than us first gen folks so that may be why there seems to be different results.