When I have insured a car I have never been asked what factory fitted options are on the car. MB can only benefit from options fitted as they make the car more desirable when selling on and at no cost to them.
When choosing a car you have a set of basic requirements that have to be met. Once this criteria is fulfilled it is a case of what your personal budget will allow to include any additional luxuries. We pay a lot for these cars and need to be happy and comfortable for the 3 years we have use of them.