Overclockers Club published a review on the XFX R9 290X Double Dissipation
A quote from the article:
Priced at $649 as of the date this article is published, the XFX R9 290X DD is selling for a premium (much like most AMD-based cards recently, thanks to cryptocurrency mining) over the R9 290X launch price of $549. This puts it price-wise right between the GTX 780 and GTX 780 Ti price points of $500 to $700. At that point, you have a tougher choice making that call. If you are looking for a R9 290X, the XFX R9 290X Double Dissipation equipped card is one that addresses the short comings of the reference design and looks oh so much better doing it. It's cool, it's quiet, and it easily delivers excellent FPS with high settings.XFX R9 290X Double Dissipation Review @ OCC