I have a D4..... love it.
Servicing & repairs aren't cheap, but I knew that when I bought it. If I wanted costs on a par with a Citroën c1, I'd have bought.... err..... a Citroën c1.
Car is spacious, comfy, capable, works as a family car just as well as a shoot wagon, can get mid 30s mpg on a steady run.
Is it faultless? No. But the pros outweigh the cons.
Do I regret buying it? 4 years on, absolutely not.
It has had logs, bricks, deer, dogcage, people, guns, wellies, suitcases in the back (not all at the same time

), but just wafted along the motorway yesterday as we crossed the pennines to visit my daughter at uni.