I am in the process of buying a 182 Audi A4 and am looking at 2 demo/ex service cars. One of the cars is 2 litre TDI 122 bhp 50th Edition Manual and the other is similar except it is 150 bhp. I prefer the colour and look of the 122 bhp car but am concerned it might lack a bit of spark. The 150 bhp car is €1,500 extra to but. Do you think there would be much difference between the two? Does it make much difference which I buy? What are my options re remapping either car to improve fuel efficiency and in the case of the 122bhp to give it a bit more spark? is it possible to get improved fuel efficiency and more power in the one re map? Is it as adviseable at all to remap? Might it invalidate warranty/Insurance.