Physical.
Because everybody except Nintendo makes proprietary memory, digital actually comes with a hidden expense. You have to buy memory to fit the game onto, and usually at a hefty premium. Sony memory cards for the Vita, for example, are four times more expensive per gigabyte than the conventional SD cards the 3DS uses. Console hard drives are the same way, but not quite as expensive. By extension, installing from a disk takes less time than downloading on the internet. It's not even close unless you've got something like a T1 line.
Digitial is also just flat out more expensive, too. It doesn't directly compete with used games the way a physical disk would on a shelf. New physical games are usually within a few dollars of the used price at a retailer. Digital? Almost always more expensive.
Does digital keep your collection organized? Sort of not really. If you have anything beyond a basic collection you will spend as much time browsing through your digital shelf to get to a game as you would thumbing across a physical shelf and putting a disk in. You really have to be lazy to not be willing to get up off your couch for the two seconds it takes.
The only real advantage digital has is it reduces physical clutter. As someone who has moved recently, I appreciate reducing physical clutter, but if this is only relevant to people who are moving, it's reasonably special case. Sometimes people argue about scratching disks, but I haven't scratched a disk in ten years.
Digital's big weakness, though, is that I can't lend it out. Even single player gaming is a social activity you share with friends. You talk about goofy adventures, weird plot twists, and game-breaking glitches. Making it so I can't lend a friend my copy is a major value lost.
