And Tesla is obliged by law to deliver parts for the roadster for, I think , 10 years. So it would be a clever trick for Tesla if they could adopt some parts of the Model S technology to the roadster. I'm thinking e.g. battery or charger. If in some 5 - 7 years some 1000 Roadster's need battery replacement and Panasonic does not produce any Roadster cells anymore, and that is already for years, what will Tesla do? So it would be a clever trick to offer a better battery pack with technology of Model S. Easier for Tesla to produce, they can ask more money for it as it is a better battery, they can oblige to the law and they have a marketing winner: Look if you buy Tesla you are safe to get a car for the future!