Nothing is harder than Black. Debbie had a Volvo V40 with a pearlescent Black with a subtle color flip depending on how the light caught it. It looked great in the showroom but what a pain. In Atlanta, it also turned the car into an oven.
I bought a DA buffer for it and endless bottles of various grades of polish, swirl remover, wax, swirl free polish....
I vetoed Monaco Blue for our e83. It looked great in the showroom but I knew it was going to be too much work.
The e89 is a more manageable size. I know DSB is going to be work but the car just looks so good in that color.