Originally Posted by WhiteRabbit

On cars that are delivered with 'dino' oil you need to wait to switch to synthetic oil so that the piston rings bed in correctly, otherwise you will get increased oil consumption. On cars that are delivered with synthetic like our SLKs this is not an issue as they are designed to bed-in using synthetic (the exception being a few early 05 SLK 350s that had oil consumption problems due to faulty piston rings).