Lucian Ad or Crit??

what is better on Lucian, Ad or Crit. I used to play Lucian ad and he was good, but i needed to hit my q and all my abilities, but i feel like i do alot in team fights. But with crit Lucian, you have ad, and have a lot of crit damage, so your flexible if you miss your q, your if you miss your ult, but then you lose a lot of range, but which is best?