My wonderful spouse insisted we keep the car when the question arose, so we had the modifications done and accepted the check for the estimated added depreciation. As time goes by, the local dealerships seem to have lost track of the TDIs, and the extended warranty that went with the modification. Even so, one of our daughters has taken to the car in a big way, and wants us to give it to her. In any case, it is staying "in the family" for the foreseeable future.