I personally wouldn't go out of my way to buy them and install, however, they actually look nice once installed. Don't paint them but keep them black as they are so they remain obscure. I wouldn't want the mud flaps to be too tacky and be the main attraction of the DS design!
Having just purchased my first Disco 4 and very impressed as the ride is soooo smooth on country roads - I was dismayed the mud flaps were not standard within the purchase price.
However, reading these comments it appears people are concerned with the look of the vehicle with them installed. If one lives in the city why bother and obviously if you're not doing any serious 4WDriving and looks are more important I can see why mud flaps are not wanted!
I live on a property in the southern tablelands. I've only had my new LR for 4 days and already due to the environment, the side steps are now a depository for mud and debris.
So I've decided to have them fitted. If anyone can share a photo of a Disco WITH mudflaps for comparison it would be appreciated.