HD5970 in 2015 - time to upgrade?

[Smart3]

Hello. Early adopter of the HD5970 here, and I really like the card.

Should I upgrade? to the 970 or later in the year with the R300 series?

Budget: no more than $350

Here is my rig for your consideration:

Spoiler

Manufacturer DigitalStorm Online
Processor Intel Core i7 960 3.2GHz (Quad Core) (Fan: CoolerMaster V8)
Memory
Kingston HyperX FURY 16GB Kit (2x8GB) 1600MHz DDR3 CL10 DIMM - Black (HX316C10FBK2/​16)
Hard Drive 1x Samsung 240 EVO SSD
1x (1TB Western Digital (7200 RPM) (32MB Cache) (SATA) (Extreme Speed)
Motherboard ASUS Rampage II Extreme (Intel X58 Chipset)
Operating System Microsoft Windows 7 Professional (64 Bit Edition)
Video Video Card ATI Radeon HD 5970 2GB
Physics Card No
Monitors Samsung Touch of Color T240 24" LCD Widescreen Monitor - 5ms, 20,000:1 Dynamic, 1000:1, 1920 x 1200 (WUXGA), 300nits, DVI,HDMI, VGA, Rose/Black + Samsung 24" (2014)
Sound Sound Card SupremeFX 7.1 - Creative Lab's X-Fi
Mouse Razer Lachesis Gaming Mouse, 4000 dpi, Banshee Blue
Mouse Surface Razer Destructor Gaming Surface
Computer Case Cooler Master HAF 932 (Black OPS Edition) (1000w Corsair HX Silent Edition PSU)

 

[Calculagator]

The 970 should get you around 2x the performance in modern games at high resolution and use much less power. Still no telling what sort of performance the R300 will have for the price. Things will always be faster and cheaper in the future. If I were you I would wait until either I needed the extra power for a certain game or until the new cards come and prices drop.