4-matic? Or not? Looks like you've loaded it all on  Congrats! Keep us posted.i just ordered my Pewter Silver c320 with auto tranny, C2, C4, heated seats, teleaid, comand system, drivers multicontour seat, nav cd collection, AMG wheels. Should have it Dec. 
$1800 extra, I think. Not that much at all considering that it is the price of a couple of sets of winter tires/wheels. Did not order the 4 matic. Dealer said I can order it but it was totalling around 47 grand. It's almost c32 league so I dumped it. It doesn't snow much here anyway.
The C-class is definitely more fun to drive than the ML (if you can imagine that, LOL), even more nimble. It rides softer too (far more refined than a Camry), but yet is firm enough to be sporty.I can get a ML320 for the same price. Doesn't seem right. Still not sure which way I'm going to go.
The system is only about 150lbs, if not less, therefore it's like having one extra person onboard. Even the M-class' permanent 4WD system with low range gearing doesn't weigh 300 lbs.The 4matic adds a lot of weight to the car...I think around 300 lbs. Which will affect your performance. I once read that the added weight of AWD systems without snow tires causes longer stopping distances in rain and snow as compared to similarly equipped FWD/RWD setups with snows!
In that case, you'd better not get rid of the ML [:0][!]That's the problem. I have a ML and a C Coupe, plus a lot of miles on the autobahn in the C Sedan (see my other posts). I agree, the C is a lot of fun to drive and they are very different. Since I just got the coupe and the ML is four years old, the ML is up for replacement. The original plan was to keep the ML forever, especially since they dropped the skyview top, which we love. But, so many improvements have been made that the ML feels like an antique compared to the C.