I previously owned a Mazda 3 Diesel and wanted a slightly bigger car. I really wanted a used Mazda 6, but at $20k+ a for 60k km 2008-09 vintage model, this $14k+ Sonata made too much sense - there's no safety or convenience equipment missing from this car, so well equipped it is. And its interior dash is one of the classier dashes.
I love the external cantilever mini boot hinges that do not stupidly intrude into boot items when closing (Hyundai take note - why did the replacement i45 revert to goose neck hinges??? Shame on Camry too). I enjoy the quietness of the car. I appreciate the ride which is firm but supple. I also appreciate the fairly direct steering. Engine is averagely economical (10L/100km in city, 8L/100km highway) and OK when pedal to the metal.
Its 5-spd auto trans is generally good (changes smoothly and intuitively) but can be a little stuttery between 1-2 depending on engine speed and temperature (Hyundai says it's OK).
The steering while direct, has no feel, which sucks - harder to keep the car in lane in the twisties when you can't feel where the wheel is pointing. Roadholding though surprisingly a little better than my Mazda3, despite Hankooks.
Overall, very much like a Camry, except better build quality (IMO) and presentation, a bit quieter, cheaper and with remainder of Hyundai's 5 yr warranty, just makes so much sense (but don't expect it to stir your heart!).