Absolute performance isn't even a given considering the whole driver stack thing. It's really hard to pick AMD over Nvidia for any reason these days, which is one reason why AMD's discrete GPU market share is falling fast towards 20% while Nvidia's is going to be north of 80% soon. Anyone who buys AMD now should be thinking about how much longer they'll even have driver support when the company is
sinking inexorably towards insolvency.
The concept of price/performance is muddied in the land of discrete GPUs because of the many other factors which may play a part in deciding which card to buy. Ultimately winning the benchmarks by a few FPS one way or the other isn't as big a deal as it might have been during the days of Quake III. The recent HardOCP review of
Radeon Fury X CrossFire in 4K is proof enough of this, sure the average framerate is higher in some games than 980 Ti SLI in 4K but that's meaningless when the game is a stuttery mess on the Fury X CF setup.