Just finished playing a couple of hours..
Ran ok for me, though I had no raytracing on and I only have a 1080 GPU. The animations were really weird, it was like there were frames missing in the animations, like you would vault over an object or jump down from a ledge and it was just like there were sections of the animation missing. Think of a flicker book drawing thing and then some of the pages are missing. Was very noticeable.
London was good, cool that you can ride on the london eye. Overall the presentation of the city of London was good. Graphics were fairly decent on the city itself but pretty god awful on the characters, every single one of them were ugly models, looked like character models from 5+ years ago and the whole gait and movement of the characters was terrible, like they all had arthritis and were bent over. The voices (as a UK native) really began to grate on me after a couple of hours, every one was like some Dick Van Dyke parody of what foreigners must think we all sound like. The game has quite a lot of spelling mistakes too, especially noticeable in the subtitles, in the first couple of hours of play I saw so many basic spelling mistakes. City traffic unfortunately succumbs to the usual vehicles being stuck for no reason at junctions. The npcs actions just dont really make much sense, an npc will get run over by an npc car (because the vehicle pathing has just gone wonky) and then they will get up and walk off as if nothing has happened, even more odd is that a number of times I saw cars just drive into each other and motorcyclists getting repeatedly knocked off their bikes by npc cars and the rider would get up and just walk off down the street , leaving their bike there.
The play as any npc seemed to work well and it was good to see that they were actually fairly different in terms of skills/abilities, although in the end they all seemed to play much the same. Also it appears that 1 in 2 normal British people in the street have access to fully automatic weapons, which struck me as somewhat odd. It was pretty funny in the first pub to hear Skinner and Baddiels 3 Lions being played
Biggest problem imo (take into account that I'm not a fan of GTA), is boredom. I've just logged out, after only 2 hours of play from moment of release and already I was starting to get bored. London is done very well as I say and the play as any npc works well (I can see more games in the future using and further developing this mechanic) but after just 2 hours I was already thinking meh, had lost interest in the story and missions and was already beginning to just mess about for the sake of messing about, running people over, gunning people down etc just for the ***** and giggles of it. I could see myself getting bored to the point of not wanting to play very quickly and I think that non-GTA fans wont stick with the game long.
Also, expect to see hundreds of youtube videos about the seriously Wonky physics in the game, if you are looking for a game to make a funny physics youtube video on, this is your game, so many bizarre things happen with the vehicles and the ragdoll physics
Overall (and as I say, take this with the caveat that I'm not a fan of GTA, which I guess this is "similar" to) not a good title for me, I'd probably give it a 5 or 6 out of 10 (primarily for the depiction of London and the play as any npc mechanic which I think in years to come will really develop in gaming) , glad that I got to play this as part of the Uplay+ sub rather than for the retail price.