I can't really tell you which is the best DD job, but I can share my experience on Pugilist, Marauder and a little bit Lancer with you.
I started as a Pugilist as my first DD class in both beta 3 and open beta. When I'm playing my Pug, I would run my char to the back of the mob while attacking it and when the mob turns to me and before it perform its attack, I'll try to move to its back again. In a way I think physically moving the char to the mob's back would increase the evasion rate, I maybe wrong, but that's how I feel. Also, blasting my Concussive Blow from the mob's back seems has higher successful rate.
When I played my Marauder, on the other hand, I would just stay in front of the mob. Since Marauder has a front aoe (affect mobs in front of you in a cone shape) regular attack and an aoe special attack (all the mobs around you), I would usually put 2~3 (depends on the mob's level) and kill together.
When I played my Lancer, I would say she kills faster than Pug (my Lancer was only rank 8, so it maybe different in the future), but now as strong as Marauder because I can't link 2~3 mobs at the same time. Their only aoe skills before rank 8 would be Skewer, which I learned it at rank 2, it'll hit 2 mobs in front of you.
If you want to play DD class, I would suggest you start as a Pug or Marauder, because you could get Second Wind (self heal) at Pug rank 6 and Bloodbath (self heal, amount based upon your next successful attack) at Marauder rank 6. With these two healing abilities, it's so much easier to start a new DoW class.