Imo Darius has the advantage in lane against Jax. Q does so much damage that Darius can afford to not auto-attack Jax for a ciuple seconds.
Jax could win a 1v1 at higher levels(12,13,14-), but in lane he just doesn't have the damage. --- If you believe in Jesus Christ, have accepted Him as your Lord and Savior, and are 100% proud of it, put this in your sig. g-cube's Vice President of Cakes.
We can't invite scenarios into this without coming up with silly points, so i'll concede what I wrote except as an example of how Jax is meant to harass. I concur with your point that it's mostly up to who begins to punish and if Darius decides to do so early on with early points in 'Q' then Jax'll have a lot of problems unless Darius does something dumb and/or gets ganked. We'll see how it plays out when Darius gets re-worked though I'm still in favor of Jax winning post-6. --- R.I.P. ManCelaPedo