When I made my signature reservation I believed that there would be significant differences between the sig and gp cars. It seems as if for the performance version the only difference is the different color choices and delivery time. Is that correct? I am seriously considering dropping to the gp performance as the time factor does not justify the price differential to me. Am I missing something? An added benefit of waiting is the potential for clarity on a center console and possible 19" wheel credit. Thanks for your help.