redciv1, you are absolutely right. So far I have upgraded to 17X7 wheels with 255/50 tires.
The springs lowered the car about 1 inch, looks better but as you have figured out, no better handling.
I'll be upgrading the struts next but I'm thinking that the springs do not provide enough support. If I put anything in the trunk it SAGSSSSS bad.

thanks for the info,

Phil
2009 Sonata
2008 SI