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There is a significant amount of overlap between the different OG editions - OG12 and OG13 share approximately 75% of their questions.
The old paper tests are so old that, no, I would no longer use them myself or recommend that others use them. (The last time the test was given on paper was in 1997...)
The best path is to start with OG13. If you need more questions, then buy the question pack associated with GMATPrep - that contains about 400 more questions. You shouldn't need more than that - if you do, it's because you haven't really been studying what you had in the first place. So make sure you're not just plowing through thousands of questions without really learning from each and every question!