I've ordered and returned one of these by accident - it was a Powercolor 7870 Myst+ edition or similar. I'm sure performance is superior to the 7870 but power consumption, board size, thermals and noise are not.
It was my fault for not checking the product specs - but these are truly bottom-of-the-barrel, massively defective Tahitis that need high voltage to run even in their cut-down, defective state.
If you don't care for size, noise, heat, or power consumption you have yourself a performance/$ bargain.
Unfortunately two of those criteria were dealbreakers for me.
Some people ask me why I have always enclosed my signature in spoiler tags; There is a good reason for that, but I can't elaborate without giving away the plot twist.