Go get 'em Bigshot! They obviously were just going to play footsies with you until you decided to play hardball!
Oh well, they forced you to play the "lawsuit" card! From what you've stated so far, I think you've got a very good case, and a pretty good shot at getting everything you want. They will probably settle out of court, unless the GM cuts his losses and gives you your money back...
2009 ML350 (84K) - Family vehicle
2001 CLK430 Cabriolet (71K) - Wife's car
2005 BMW 645CI (124K) - My daily driver
2012 Mustang V6 (60K) - Daughter's car