I don't know about Spain but here in Luxembourg I had to change the lights as the local test requirements are strict and need an LHD assymetric beam. You will also need to buy an EU rear left light and have the car reprogrammed (or hard wired) for the rear to work correctly. If you do both it works perfectly with programming. I got my headlightsfrom eBay for adjust over 1000 euro. Mercedes is the only place that can do the car programming as it's linked to their online data card.