Listen to the General. You cannot move apps to the cards, because they a Windows File systems, so you cant run Linux programs on them. You have to convert and boot for a card in order to use all that extra space.
Yes, if you want to get in deep, it's worth it. Look at my sig links; what we're talking about is cloning. Penguinbait has made it easy. It's not that you "free up space;" you create a partition that can be as large as you want.