I just purchased a 2003 S430. Can I replace my navigation in my 2003 S430 with a newer navigation unit? I'd like to either get a DVD Nav system or a nav system that has the data stored. Also, do the newer Nav systems allow you to play a freaking CD in the head unit while the Nav is on?

On a side note, does anyone want to give me some feedback on purchasing a waranty covering my car for3 years and 36K miles? I have 60K miles on it now but not sure if the waranty is worth it or if it is even needed..... (Waranty price=$4,500 with no deductible.) My door and trunk vacumes have been reset twice and the dealer said that alone is $600 and $800.

Thanks,
Ron