My Sentra is now 12 years old, and I've had it for 8 years now. It's still fairly low mileage at 130k. I've also tried to ditch it many times before but never had a good reason to do it. It gets still 30+ mpg with automatic transmission. Interior is starting to deteriorate, such as fabric detaching and shredding. Other than that, I've never had major mechanical problems with it. Had to replace ERG valve, IAC valve, 3rd set of tires, 2nd pair of rotors, on 3rd battery, plus regular oil changes. Alternator, transmission and timing chain are still going strong. I have no complaints as it's taken me from college to graduate school, and so far all 5 jobs I've had!
Reliability, fuel efficiency, peppy at low speeds.
Cup holder blocking the radio, interior fabric quality, rear bumper doesn't stay attached fully (seen this on many other Sentras).