I've got a 2006 Sonata. DO NOT get the Scosche HY1609B. It does not accept a
single DIN radio.
http://www.scosche.com/scosche_caraudio.aspx?ItemID=HY1609B&CategoryID=5
They expect you to put the radio in the upper opening, and it simply does
not fit in the assembly. Their tech support was worse than useless. All they
kept telling me was that the had pictures of the prototype. Never mind that
the production version is screwed up. I wasted $20.00
I think I used an American International kit. The harness I used is for late
model fords. You'll need to make sure you apply power to antenna amplifier
pin, and the harness does not do this for you.
Other than the problem with the dash kit, no major problems... Be prepared
to find all the white clips that will come off the dash trim when you remove
it. They fall back through the holes into the dash. I put a Pioneer 4900 in
it, and it sounds good.