I have had this car for almost 7 yes and only had to do a repair once, and that was for the brakes. Best car I ever owned, and still rides excellent, not a noisy car, when idle it seems like it is off.
My 2007 Sonata was my absolute favorite car I've driven. It handles very smoothly and has good maneuverability for its size. We had the V6 3.3 L engine and boy was it responsive. It was eager on the gas, ready to accelerate at the drop of a hat, just the way I like it, with solid brakes as well (way better than the ultra-sensitive brakes on our Elantra). I loved how lively it was, a joy to drive. Friends who have driven it agree it has a great feel. I think we got it around 80k miles and traded it in around 120k. We bought this car used while I was in college, I used it for 3 years out at school, where it endured harsh lake-effect winters. The trip to school is 600 miles each way (a trip we made 4 or 5 times a year) and the Sonata takes to the highway like a champ, even with multiple passengers and a trunk full of luggage. The cabin is spacious and the trunk has plenty of room - sometimes we carpooled the 10 hour drive home with 5 people and all their stuff! The only problem on those trips was in the winter the passenger footwell was always FREEZING, we had to plug it up with pillows and blankets; we think air came in straight from outside instead of going through the heating system. One of my favorite things about the Sonata is the common-sense controls on the dash - radio and air are straightforward and you can get what you want without even looking. Only problems we ever had before we traded it in were bad electronics in the sunroof, but it was after-market, and the cable for the driver window (easily replaced). Finally got rid of it after three years because of a leak in power steering that we would've had to replace the rack for. But we traded it in for a 2009 Sonata!! And now that car (almost exactly the same but with minor improvements) is our workhorse for the college kids. On another note, the 2006-2010 Sonatas look great! I hate the new version, they've ruined a beautiful car. But for that sweet spot of years, the Sonata is the best car out there. Looks, performance, spaciousness. It has it all.
These cars had engines with faulty timing chain tensioners; they can fail with no warning and cause severe engine damage. My Mom's 07 Sonata had 127,000 miles and had a timing chain slip, causing cylinder head damage. Hyundai has been sued for the 2010-2011 models (for the exact same problem), why they got away with the 2006-2009 models is a crime. If you complain to Hyundai, they either ignore you or try and sell you another POS Hyundai. Stay away from these junk heaps.