In my experience, XFX is a low-to-mid range manufacturer.
Not someone to completely avoid, but not as well built/designed as the top-tier cards tend to be.
Power Color is BOTTOM tier cheap - might last a while if you don't even wave the thought of overclocking at them IF you're a bit lucky.
IMO stick with the better folks for mining, Sapphire Gigabyte EVGA perhaps MSI.
For my mining, I underclock and undervolt, so there is no need a good quality overclocking cards at all.