Are Vibration Plates effective?

[kinkytinch]

I saw a machine in a mall wherein you just have to step on a vibrating plate. Seems easy and I'm intrigued. After a short try, I felt my tummy ache as if I ran for 1 hr on a treadmill.

Have you tried it? Is it as effective a doing cardio on a treadmill?  Is it effective in general? How?