only thing I noticed with going with the thicker magnacore wires was less ignition interference with my sound system they do have a lot better shielding than stock. Other than that, no performance gains. Although the color matches my red/orange/yellow "my engine's on fire" color scheme

 

I've got them and they work fine.
Hard to tell as I believe you have to tune the 4G94 to really tell if it's done anything.