I bought with about 58k miles. Very good ride and fuel mileage; strong and plenty of power. Seemed the perfect car until 68k miles. Between 68k miles and 72k miles replaced transmission, air struts, and fuel injection pump. I rated down the reliability due to the mechanical failures, but now repaired, I am back to trusting it's dependability. The problems were caught before breaking down on the road. Transmission metal and seal fragments were found on filter and oil change; struts were flat and wearing rear tires severely and unevenly, and; fuel injection was causing erratic and surging RPM, and a couple stalls.
I like the tireless comfort of driving long distance and gas mileage of the NorthStar. The size and handling give a feeling of safety.
None. This particular car seemed to have major mechanical failures not typical of Cadillac.