Article directories aren't much helpful as it was before. Try submitting the articles to Web2.0 properties such as squidoo.com, wordpress.com, blogger.com, hubpages.com and others. Try to make 10 of them, each property containing 1-2 articles. Target related keywords that has low competition in your article on web2.0s and try to rank those web2.0s using high pr comments, other web2.0s with spun article, bookmarks, etc as your tier 2 [can use fiverr for tier2 links]. Once in a while, do some guest posts as well. Moreover, if you got the money then creating your own private high pr blog network is really powerful to get your site rank.
You can add Article unique quality content into high PR directory sites. if it allows you to submit links then only it becomes helpful to you, so you can add articles in that kind of directory submission sites.
If you have genuine unique content, you will submit for high pr article. This is no problem for Search Engine. So you will check duplicate or spun article.
you can submit article in article directory, Article submission is very important in search engine, it give us good traffic and back links, submit fresh and unique article, not duplicate. If we submit duplicate article, this not good for search engine.