I have 20,000 miles on my new Sonata. It's been a great car to drive so far with no major issues. I've obtained fantastic gas mileage (37mpg) by combining the ECO mode, cruise control and a nice long highway. The paint is sexy and durable. The fit / finish is solid without any noticeable defects. I've been completely satisfied with my service crew as well.
--Gas mileage (22mpg when letting loose, 37mpg granny-style)
--274hp and it'll snap your head back off the line!
--Great looks. I've gotten MANY compliments from total strangers. They approach by saying, "That's a Sonata?"
--Panoramic sunroof is super cool!
--Bluelink. $179/year gets you remote start, SOS and lo-jack engine disabler that lowered my insurance cost!
Build quality is nice inside and out although I'm seeing some slight wear on my beige, leather seats. I'm also experiencing a slight engine burp on occasion, but forums suggest a quick re-gap of some spark-plugs will fix that. I've also noticed an anti-freeze scent from the air vents but nothing more than faint. Finally, I noticed that the vehicle under-steers a bit. Nothing uncontrollable though.