40 ohm wires are usually not that common in cars with a lot of electronics, too much RFI induction, the 350's are pretty low too but you wont tell the difference between the two performance wise. Accel's were like 600/ft.
Basic electrical knowledge of Ohms law applies.
I have people argue this with me from plug wires to electronic cig vap coils. The “Ohm” is a measurement of resistance. Less resistance the quicker the energy can travel requiring less power from the sorce to complete the job. That is less effort.
On the engine performance front, your going to need a super sensitive machine to show anything. But it is there. It may not translate into anything meaningful hence why people say it is bunk. But it is less stress on the electrical parts.