Actually, the XFX unit is likely to be capable of being overclocked beyond the performance of the stock Powercolor card, for less, and is a higher quality card in general. Powercolor is a second tier manufacturer and while both XFX and Powercolor are Taiwanese manufacturers, I've had much more trouble dealing with Powercolor support than I ever have with XFX, in the event support is needed.
Idealy, I'd go with a Sapphire R9 280x card and they're currently fairly cheap.
PCPartPicker part list /
Price breakdown by merchant
Video Card: Sapphire Radeon R9 280X 3GB Video Card ($209.99 @ Newegg)
Total: $209.99
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2015-07-27 22:21 EDT-0400