It's firmly in the sim category. Anything arcade-like in the game would be unintentional.
sim, but not up there with rFactor 2, iRacing, Automobilista and Assetto Corsa. It's very much on the easy side. And, please nobody tell me this "difficult doesn't mean realistic", we're talking about stuff that has Pro versions used by professional racing teams (AC and rF have, rFactor Pro is still used as the base for customized Formula 1 simulators used by all F1 teams).
Project CARS feels pretty damn awesome in my opinion though. The too fast lap times from Project CARS 1 are dialed down now too. It's easier to drive for me, mainly because the FFB is better, but I'm actually slower than in pCARS1.
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Now what I really wanted to say:
My biggest problem in pCARS1 was the braking. There were cars in pCARS1 that suffered from tremendous, insane understeer under braking even with a very rearward brake balance and even if no wheel actually locked up. Other cars were the other way round, the became super unstable and began to rotate with the slightest steering input under braking.
Half a year ago I wrote down 4 extreme incidences of this behavior with car/track/corner-name to check if this is still an issue in pCARS2. And actually they are either gone so very very dialed down, that my brain can believe them.
However, I just drove the McLaren P1 and that car was pretty unstable when trailbraking hard and become more unstable the further I shifted the brake balance to the front. It seems that when the inner front wheel locks up in a turn, the car turns in
more, instead of less.
Also, electronic driving aids: The ABS (which I tried in the P1 as well) is working, but
super low-tech and I found out that it's like that in all cars. Even race cars that have modern ABS. The traction control simulation is the same. Stability control is probably also more high tech now than what is presented in pCARS, but no other sim does that right, so that's forgiveable.
I think I'll keep all assists off in this one, even though I think it's stupid attitude in general and would never get this idea in Assetto Corsa for example. Maybe I'll keep a very low TCS in some cars, even with low-tech that can still make you faster in some cases I guess.