Other than looks (and if you have the engine cover on, that covers the wires) there is no performance advantage for exotic wires. Only if you have old wires that are worn out will it help, and even then, stock wires would work just as well.
MSD helps older cars but for the modern computer controlled cars, I don't think you will see an advantage, especially on a stock or mostly stock car.
Where MSD helps is with wild cams, high octane race fuel, extreme advance on ignition and wild compression ratio's and blowers (turbos). Under these situations the combustion chamber is not a friendly environment for spark and combustion, and every little advantage is a help. But in mostly stock cars, even pretty hot ones like the Hemi and SRT-8, the tuning is still pretty mild.
I agree with others, spend the money on a better sounding exhaust that might be a little lighter and might make a couple HP.