I have found a great website that discusses  Whole body vibration machines and the crazy fit machines are no good for anything but massage and relaxation. They tell us that for one the crazy fit machines ar every cheap because the motor in them does not allow the machine to reach a Hz (speed) level of more than 18 HZ. All the studys out there done on tilting vibration plates like the crazy fit say that machines need to reach at leat 26 Hz for muscle tone and training! The crazy fit machines also do not show the speed in Hz they usually show the speed in level from 1-50 or 1-30 and these are usleess if you have reseached at all the industry before buying a machine and found out that Vibration training is frequency specific, meaning there are recommended speeds Hz that are best suited for differnt results. That being, balance, relaxation, training muscles, and toning muscles. I would strongly recommend you look at the website www.hypervibe.com.au they have great information and also sell an instructional DVD which has been designed by health experts.