congrats! sounds like a great car. i am looking at a 2000 S430 myself, my E420 wants a garage mate.

the most common W220 problems are: airmatic failure, instrument cluster going out (MBUSA official recall), rust, and of course the electronic system.

post some pics!

__________________
Current cars:
2001 MB E55 AMG
2003 Honda S2000
2000 Honda CRV

Gone but not forgotten:
2004 BMW 325i 5sp sport
1999 BMW 540i sport
1997 MB E420
1995 BMW M3 coupe