Ford Mustang gt 2015 or Mercedes

Moin Moin, I can’t decide… please couple ahead and downsides for each vehicle who has a bit more clue than I do So I’m standing in front of 2 cars C63 AMG BJ 2012/2013 Full with about 40,000 KM 487 hp fear of giant worth loss after 3-4 years. approx. 20,000 euros (because of new model etc.) or Ford Mustang gt 2015 Premium US version and then slightly remodeling possible slight performance increase and definitely exhaust change to x2 tube back . Value loss is definitely lower than be in c63. Thanks for your help, time and tips !!! Best regards Dimitriy Foth