I take tp every single game. I just find that its useful in game. Darius has two matchups. He snowballs and destroys everyone or he completely gets destroyed in lane. Tp is useful to get around the map if you snowball and useful to get back to lane if you get destroyed. I have never played ignite, but I win lanes against other dariuses with ignite. Don't take exhaust. Like its a waste of a summoner for darius. He tanks so he takes like no damage and even if you take some you can get it back with q. He also has plenty of cc so its useless.