If you do much driving on rough roads be prepared for a hard ride. Otherwise I love this car. Roomy, easy to drive, great in the snow, handles corners beautifully. Would like it a little less road noise but not too bad.
2010 Hyundai Sonata SE V6 4dr Sedan (3.3L 6cyl 5A)
Just wanted to add my experience to the list. Have had 2 outside door handles break off. Owned maybe 20 cars in 45 years, never had one door handle break off until this one. Have trouble reading the clock in the daylight.
2010 Hyundai Sonata GLS PZEV 4dr Sedan (2.4L 4cyl 5A)
Car handles well in all weather conditions. Comfortable to drive. Good visibility. Lots of room when rear seats folded down. Car has good balance, low tire wear. I have 128,000 km on rear tires and don't have to change them yet. Front tires changed at 115,000 km. No problems from new - One warranty issue to have transmission re-programmed - solved rough shifting that had developed. Quiet on both city roads and highway. Dash is great, easy to read, and controls very accessible. Almost feels like a full size car inside.
Have purchased 2013 Sonata GLS and have kept 2010 as a second car. Very reliable.
2010 had some design changes from prior yrs, Good looking auto. Good steering and braking. Lots of room in front and back seats for tall people.
Rear seats fold down and yield large storage area. Trunk has easy access for larger items.
Seat bottoms a little soft for sport model. Firmer seating would be a plus.
Could use stiffer springs on doors. If park on a slight grade doors have a tendency to not stay open fully and close on you when you are trying to enter or exit car.
No other improvements suggested.