If your main interest is CD based games, then either the original TG-16, or Duo units will play them fine. The big difference is the fact that you'll need the right system cards (2.0 or 3.0) for the original unit (which are near impossible to find), but not for the Duo. However, the original TG-16 unit with the CD add-on is a much more durable system than the Duo, which seems to always quit working. For playing Hu-Card's, you'll need a converter card for either system, and those are just as hard to find as the others are.