To start off, this in NOT a review of the car buying experience as mine was very pleasant, this is about the service department.
The last time I brought my new Sonata in for a service, I made an appointment on BlueLink from my car. When arriving for my appointment, the department had no information on what I needed done. My vehicle need its first oil change. It has also had the constant issue of the panoramic sunroof wind deflector coming unglued and popping out of the vehicle, an (from my moderate mechanical knowledge) unbalanced tire, and a malfunctioning speaker. I told them about the issues like I did to the BlueLink representative and was told they would take a look at everything, but there was a FOUR HOUR WAIT. I then had to have someone drive another vehicle for me to the dealership so I could get other things done, since they online have a shuttle service. My appointment was for 0900 and I received a call at 1400 letting me know the vehicle was ready.
When I arrive, they let me know they changed the oil, couldn't find a balancing issue, fixed the sunroof, and told me I needed to turn the bass down so the door doesn't rattle. (I paid for the technology package so it included a very nice Infinity 7 speaker sound system.) Needless to say, the car still has an unbalanced tire/wheel bearing issue, a door that rattles at -4 bass and a sunroof I cannot open because the wind deflector popped out again after a couple months.
Overall an unfavorable experience.