Are performance coil packs worth it?

I am looking at a 45,000 volt DIS coil package but unlike the aluminum electrodes on the stock coils the performance coils all use brass, brass is about half as electrically conductive as aluminum and no one in tech support can answer why they are advertising brass and being more conductive. The stock coil system is 38,000 volts so my question is whether or not there will be a reduction in the performance coil running at 45,000 volts with half of the electrical conductivity aligned by the electrodes? Do these things really work and are they worth the money?