[Konstantinos]

That would work if you used a timer and you checked if the player is in range so you would teleport that player but.. it's better not to use many timers.

I believe that either with a command or a key is fine.

EDIT: What DarkLored suggested is also nice. Streamed checkpoints* though so it won't show in the minimap if you're not streamed to the checkpoint.

*By Incognito's streamer