To respond to The OPs question. and perhaps amplify the points of RussianSensation let me start by saying in addition to my rig listed below, I also am running a 3770k @4.5 Ghz with 2 EVGA GTX 670 FTWs in SLI and a FX8350 @4.5 GHZ with a EVGA GTX780 Classified (both cpu and gpu custom watercooled). I don't make these comments to brag, rather to hopefully avoid the accusation that I am AMD "fanboy" because of my rig below. I had exclusively owned Nvidia cards for quite sometime. My single GTX780 Classified with waterblock served me well in my rig below. However, I wanted to go SLI and at the time there was no release of the GTX980/970. I had been fascinated by the Hawaii chip (290X/290) but, due to the mining craze they were way overpriced.
At the time, I had a PNY GTX680 in my FX8350 rig -solid gpu. I found a Sapphire Tri-X R9-290 (not 290X) on ebay for @$290 delivered. I would have had to pay almost $700 for a second GTX Classified with a waterblock. I decided to sell the GTX680 and purchase the R9 290. My out of pocket was less than $100. After experiencing the performance of the R9 290, that started the ball rolling toward purchasing a second and running them CF in my rig below. I found the R9 290, and especially the Sapphire Tri-X was a solid card, noticeably faster than the 680 and very close to my Highly OC'd 780 (core at 1300 since WC'd). In addition, with 4k monitors on the Horizon, the 4 Gigs Vram of the R9 290 made it very attractive.
I found another Sapphire Tri-X R9 290 for about the same price and decided to go CF in the rig below. Had to buy 2 EK blocks (got good deal @$230 total) and I was able to move my 780 Classified into my FX8350 rig and run 2 of the 290s in my rig below. BEST decision I have made in a long while and really sets me up nicely if I opt for a 4k monitor.
No doubt the 970/ 980 have made an impact. For the $$$ the 970 is not a bad decision. Price wise, this morning the least expensive available 970 on Newegg was @$350 yet the XFX Double dissipation 290X (not just 290) was the same price.
My point is that on pricing vs features the battle is so close it's hard to call.
I have had some issues at first playing COD Ghost MP with the CF 290s. It appears COD does not like CF. It works OK for me. In every other game, Bioshock, Metro, BF4 IL2 BOS, my CF 290s really shine.
this is no knock at my 670s or single 780 just my observations.