My MINI was a dreadful buying experience and I had no recourse other than legal, which I could not afford. I learned that BMW will not act as an arbiter of disputes in their own cherished scheme, so effectively you are not buying something backed by the manufacturer. I'm sure someone will come along and say I was naive but hey.
I now have a Skoda and the service I received has been good but I think that's more to do with nothing going wrong and the inherent quality of the product...