Like any ranged champion, they accelerate at facing people solely at close combat. the same will go for Nami. If you are facing someone easy to bully on like then getting that extra ignite damage is almost a guaranteed win.
If your facing someone who can manage ranged champions like or it might be wise to have tp to help not get brutalized in game. So basically get tp if you think its going to be a hard lane, or ignite if you think itll be an easy lane.