by StaceyKoprince Sat May 21, 2016 4:01 pm
If you already have OG2015, that's fine - don't buy the new books. I wouldn't go back too far, of course - but OG2015 is not too far back (at least, not right now!).
If you don't have the books already, then I would buy the most recent version. Might as well, since you have to buy something.
Stacey Koprince
Instructor
Director, Content & Curriculum
ManhattanPrep