Like darkbreeze said the specs are still decent despite the hardware aging. It might be worth selling the crossfired cards and replacing with something like an r9 290 or gtx 970 if possible. I would say they're still keeping up but not 'future proof' by any means which is to be expected based on their age. Games keep wanting more and more hardware and hardware keeps updating constantly. Nothing is every really futureproof.
Just out of curiosity, why does everyone ask if their pc is 'better than a ps4' or a 'ps4 killer'? Chances are good that it is just based on the price of the build alone, I'm sure all totalled the parts of the pc cost far more than a ps4. If playing on a pc and not on a ps4, what difference does it make? I've just never understood that common question. I don't know if people are considering scrapping their pc for a console or for bragging rights or what. Consoles and pc's are sort of like apples and oranges, not really comparable. One plays (usually) on a larger lower resolution screen and is viewed from a further distance where the other is played on a smaller higher resolution screen up close where the resolution/clarity of detail matters.
So long as it plays the games you want to play smoothly and at acceptable framerates I wouldn't worry about comparing it to a console in all honesty. If new games are getting sluggish or becoming unplayable because the fps is slow then consider an upgrade. If contemplating a console then consider the upgrade costs of the pc vs the cost of buying a console and playing habits/conditions of one vs the other. Also consider any restrictions on games, not all titles are available on all consoles.