Well if you plan on getting a ps4 you need it for online multiplayer.
Ps3 and vita is not required however it is recommended as the free are usually a pretty good incentive. I haven't had it for 3 months now since nothing worthwhile has come out. However that may change with zero escape coming and god eater burst.
How hilarious .You just set off my trap card . Your death approaches. Playing: BL2(pc), bioshock(pc), mgs pw, soul sacrifice,ff7