Wires are wires. The important bit is the integrity of the insulation.
More important in Mercedes case is that the ends are good construction , made with high quality product and fit exactly both ends.
The important bits are the ends. The end that fits onto the spark plug incorporates resistor value of 1000 ohms.

These Mercedes models were twice to three times more expensive than your ordinary car at the time of release. I'm sure they didn't use half price products in the engines components.