IF you have a back pain, you should select Mercedes AMG CLA 45. Recently I have visited Seoul Motorshow 2015, I tried to take a seat for my back. The best is Mercedes AMG CLA 45, it has very hard seat and wonderful for my back. Next is MINI 5 door, Lexus IS250 and VW GTI.
High end package would be fine, but seats are so comfortable. Hard seat is great for long driving. It is True. Recaro is another solution when you bought MB E Class and higher.