I have processed the following picture in both colour and black-and-white. I believe both iterations of the same picture are equally good and offer a different view of the same scene. The picture is of the building that houses the remains of the Roman columns of the Temple of Augustus. The building that surrounds the columns is a regular block of flats, which in itself is very surprising!
These pictures are from my iPhone, processed in NIK Software (Color Efex Pro, and Silver Efex Pro).