As a Doberman enthusiast, I absolutely love the elegant look of cropped ears. Although some people choose to keep the natural floppy ears, it is hard to dispute that the sight of a Doberman with erect ears is the signature feature of the breed.
I respect buyer’s option to have natural ears, but if a buyer prefers cropped ears, I do recommend the following veterinarians (above each veterinarian is a picture of a Doberman whose ears they cropped ):