By every estimation, a $399 Neo PS4 clocking 4.2 Teraflops of power is going to be a better price/performance than any PC config that can also play VR by a country mile. Also, in order to stay 'relevant' with current PC tech, you will need to replace your GPU every 2 years or so. Higher end GPU's still make the PS4 seem really really cheap.
The amount of money you would need to spend to get top end PC graphics for 6 years or so would be incredible.










