Ok, so I know this is VERY soon, too soon to be reviewing, BUT I've had such dramatic effects after only two uses, that I had to write in. I have become obsessed with the Opal while I was trying to decide whether to purchase it or not, and am so glad that I finally just went for it!
Background-I take very care of my skin, I religiously put serums and creams under my eyes (and all over my face) every morning and night.
The Opal appears to be massaging away my dark circles. They are not gone, by any means, but there is a major difference. I hope that continued use will make a big impact.
I will update in the near future, but I just had to excitedly report in. If you're on the fence, go for it!
Also, I suggest you buy it at Sephora. My sister's Clarisonic stopped working so she brought it in 3 days before her 1year warranty was up, and she upgraded to the Mia2 for free- no questions asked (well, since she paid $150 for the Mia at the time, there was no price difference).