Personally, I wouldn't bother with article submissions any more. This link building method was devalued a lot as a result of the panda update last year and they are not seen as high quality links.
Added to that though, Google is on an all out offensive against blog/link networks at the moment, and to me that isn't a million miles different than article directories; So I wouldn't be surprised if they further devalue article links in the near future.
I would focus on manual reach out type links only right now, they take a lot more effort to obtain, but they are the most effective right now and I can't honestly see such links being devalued any time soon, since they are by definition editorially given which follows Google's ts&cs to the letter.
Just my personal opinion, although I'm sure many people on here still swear by article submissions.