I've bought this last week for PS4 from GAME (£14.99) and received it today. I knew many bad things was said about this game but I must admit it's not what everyone is trying to show. On PS4 the latest patch (1.10) improved the game to be running fine or at least I didn't feel it's buggy. The AI is not as dumb as people say (Dex I'm talking to ya pal). From my personal (1 hourish) experience today I can say the £15 I paid for it was a very fair price. In a relative comparison it's very alike killzone in my opinion but only downside is the physics which is a bit outdated in this game.
Also it's £15 apparently for digital version and season pass on Xbox store but then there are not much of content are coming with season pass anyway. Yet, justifying which is best for you is nothing to do with me, lol.
And lastly, CeX is giving £8 voucher on this so GAME should do a £9 trade meaning in case if you didn't like it you're losing only 95p (ideally). Sorry PS4 version is not the same price :(