Put simply, Mario Kart DS is a classic. Mario Kart 7 is the better handheld, but this game is still great. The mission mode is quite possibly DS's crowning achievement, finally giving Mario Kart some single player content aside from Grand Prix and Time Trials. DS also was the first to add the retro cups, have appeared in every mainline Mario Kart since. DS was a step in the right direction and a classic even still.