Good Luck!!
I can only say that I am so disappointed with the DVD navi system in my CL. Even after buying the $180 DVD for 03, it still doesn't know the road I live on, and its a state road.
My Acura navi is good only to get from city to city, not to a specific address. The SPIII has rarely let me down. It brings me right to the door (ok.. heheh within 20 feet) of an address I punch in. It knows all the little roads in developments too. A new development was built along side my property and its road is only about 6 months old, and the SP knows of it.
I guess what i'm really saying is not that the SP is so good, but the NAVI in my CL is so limited. I wonder if the newer ones are better?