I think this is skirting the edge of a very important point as well ...performing the Olympic Lifts is not simply a matter of deciding one day that you're going to do the Snatch and Clean & Jerk. Learning those lifts takes time under a knowledgeable instructor and a fairly lengthy period of perfecting technique (which never really ends). It's very difficult to learn the full lifts on your own and even then it will take time, a lot of introspection and probably a video camera.
For 99% of the population I think the "power" versions of the lifts are a more practical alternative (and also will probably give 99% of the benefits on a "casual" basis). Even then proper technique on the "power" versions takes time to learn and proper instruction.