just as the tittle says i'm not saying he's op and i'm not to good with the numbers but how do you toplane against him
will wreck him 
should be able to poke him, trade effectively, then W his Q or his hook.
Walk towards him when he q's would doge half the damage and the heal.
Jayce is currently very good against Darius, as Jayce comes built in with everything Darius DOESN'T want to be against.
You can poke Darius, sustain against him, knock him back if he tries to Q or pull you, and CS safely while punishing him for trying.
The trick is to kite him. Same with the other Juggernauts. The reason Darius is a bit harder is because of his pull. Save your dash/porting ability for after it hits so that you can get out of his AA range and his Ult as they are both very short ranges. Alternatively a long range AP top should work well too. The bottom line is you need to abuse the fact that he needs to be in melee to kill you and without that he will have a hard time.
Don't run like a headless chicken when he pulls you. You can run into his Q and avoid both his burst and the bleed stack.
dodge the ult
