I've had my Bluefin fitted for over 18 months now. I've had the last 4 cars remapped including a Focus ST, S-Max 2.2 TDCi and my current 1.5 ecoboost Kuga. I would always remap for the reasons mentioned above - safer overtaking and a more leisurely drive as a result due to the extra torque it provides. I have the Bluefin which enables me to remove the map for warranty work and put it back on afterwards. I have done this for the past 3 x Fords with no issues regarding warranty at all even after Fords carrying out ECU update warranty work. Not sure is the Blurfin is readily available anymore now that Superchips have been taken over. My S-Max diesel was brilliant having owned it for 11 years (10 years with Bluefin fitted) with no issues. In fact the MOT emissions reading was always actually way below the normal with the Bluefin.