I had a small dent in a location that I didn't even spot till I got home with our new car in 2014.
Rang the dealer, they looked at it and asked "Micky the Dent" to come to my house to correct it. It took him about 20 mins from start to finish. He had a bag of equipment including a mirror with I think lines on it, glue type solution and a small slide hammer. While I was talking to him he told me he had been to Merc and another VAG dealer that day. He informed me most customer never see how there cars turn up and he corrects them before the customers see them, but mine must have been missed due to its location. Either way it appears to be a common occurrence according to him and made me relax about the car.
No real need to reject, just make sure they are aware of it and noted to be corrected at a later stage to suit you. Then if its not correct to your satisfaction you can take it further.
Enjoy your new car
