430
Taken from bluesky: https://bsky.app/profile/simplyaj.com/post/3mtq6av6yp226
Plus a sidenote from this person on DS games: https://bsky.app/profile/simplyaj.com/post/3mttai4jaz22j
Not sure on the technical details of exactly how long they last, but I've heard similar things several times before.
Always depressing to be reminded of this. Haven't had many fail, but honestly haven't tried a lot of my 3DS/Vita games in a while, so who knows.
If nothing else tho, it's nice to have an excuse to revisit some things. Once you boot it up, you might find yourself enjoying the reminiscing. :)
Depending on country. For instance, in Germany it's only allowed if you're not circumventing anti piracy measures.
Im not 100% sure on the technical definition, but in general then backing up DS games would be OK but 3DS not.