I think about a field optimization or a chip tuning of my XC70 (year 2016, 2.4 D4, AWD, 133kw/181PS, approx. 84 tKm) after. Of course, you can be divided here, about the whether and above all how. Maybe you can help me to make a decision, because I belong to the drivers and less to the screwdrivers 1. Is a field change better, or a a tuning box and where exactly are the differences (for a layman)? 2. Are there any risks that speak against it (I don’t guarantee any more)? 3. Is the promised fuel savings really to be realized? 4. Vmax cancellation? 5. Which manufacturers are really recommended (Polestar, RaceChip, BSR)? Who keeps what is promised? 6. What else to consider? Thanks a lot already xc70ww