Ok
I have found a reliability index, based on What car? and insurance warrenty claims. I am glad to say the Mini does really well.
Here is the web site
Reliability Index :: how reliable is your car?
The Mini has a reliability index of 13.95
The BMW 3 series has an index of 36.00
The index average for all cars is 112. Therefore a car that is less reliable will score higher than 112. A car that is more realiable than an average car will score less.
The MINI is more realiable than a BMW 3 Series.