Sure. But that's in the past before nVidia Pascal came to the market a year ago. nVidia Pascal architecture is way more energy efficient than Polaris when the GPU core is heavily utilized. If there's a good CUDA optimized miner for a certain algo, a GTX 1070 murders a Polaris with hashrate and efficiency. And of course it should since it's a more advanced and more expensive card.

BTW, mining with Polaris cards is an absolute pain in the ass with the need for bios mods to get a decent hashrate, many different memory brands which need different individual bios tweaks, the need for hdmi dummy plugs or monitors connected to the cards, tweaking with wattool, etc.