I handle final re-acquirement transactions between the owner and veh mfg (
not GM products) and some of the reasons that the mfg will buy back or replace the vehicle are very minor, but the mfg just wants it done for a variety of internal reasons, i.e. - "squeaky wheel syndrome, newer/smaller mfg still building corporate image, pita lemon lawyer, customer loyalty, etc.
Several buyback stories I could tell about very minor problems... , but I'm restrained by confidentiality agreements.
Do some investigative homework.
Every reacquired vehicle situation is different. There are some buyback cars out there with branded titles that are excellent buys.