I've always stepped on the Reebok Step. It works fine w/ Cathe's videos. If I could get a good deal on the Original Step, however, I would replace my Reebok Step in a heartbeat. I sometimes feel I need the additional space that I've heard the Original Step provides. I also would like the additional risers to use w/ my high step.
If you're planning to store the step on its side, I will warn you that when I pick my step up or store it on its side w/ the long side vertical, the risers occasionally fall off. I think I read that others have this problem as well. So, if storing it this way, in one piece, is one of your reasons for purchasing it, you might want to rethink going with the Reebok.
Tracy