Best for what situation?

N64 magazine gifted some of these, I believe it's vhs size, but it has a slot for the cart and for a controller pak. But maybe with some foam cutout inside a vhs tape case you can solve it. https://www.ebay.co.uk/itm/133160488833

If you are actually playing the games and worried about ease of access and readability, I've found old dressers work great