Moretti hasn't impressed me with his technique, and can improve on the defensive end, but I like the fact that he has abundance of pace. So I would like to see how he develops.
As for O'brien, I too agree he is good footballer. He is versatille, pretty quick, and has decent technique.
But on the basis of World Cup, I would prefer Beasley. He has a huge potential, as a attacking full back!

Still, I think left back is not the most important position in the world, so I would concentrate on other areas of the team first. Central pariring could do with some work, as well as our midfield.
I would be happy with solid defending down on the left.
