download vs buying cartridge

[trans the psycopath]

hey ive noticed nintendo is putting alot of there cartridge games on there download channel before they become ancient like at the same time as the main release.

so ive been wandering the super smash bros ds should i download it instead of getting the cartridge. like is there any real disadvantage to the download in comparison to the physical game cartridge or changes to game play.

ps NO SPOILERS please