I would imagine on PC this is a 5/5 SIM.
On console however, specifically the PS4 that I am using which is the 500gb first edition PS4, the game has slight room for improvement.
This game is brilliant, don't get me wrong. This is the SIM we've all been waiting for on the current-gen consoles. KUNOS admittedly have downgraded the visuals to accommodate the realistic physics on the console edition... But once you exit pit lane - you don't really care.
Visually, the more powerful PS4 Pro and XBOX X would offer a higher quality HDR and smoother refresh rates I would imagine, but on the pleb machine I am using I often get tearing and "jitters" while racing, which can be slightly annoying to the eye. This isn't a deal breaker, but it is annoying when you're doing precise driving to perfect your laps. What this means is, when you are aiming for your mark on the apex the tearing or "jitter" on screen makes it seem the apex has suddenly moved a fraction, and your brain naturally tells your arms and hands to turn the wheel as a reaction. I find this causes overdriving of the car.
Not to fret, though. Supposedly, ACC will be compatible with next-gen consoles. What this means is that the above-mentioned issues should fall away, and we could even expect the same level of visual aesthetics that live on the PC version of the game. It is important to note that when playing on a console, your actual TV may need to be upgraded to support higher resolutions and refresh rates. 4K 120hz should do the trick, but you can find higher spec options. Next gen PlayStation won't play higher than 60fps, so really no need to fork out a fortune on a gaming monitor at 240hz or a TV at 120hz, although they would offer advantages in other areas. My recommendation would be any new 4K Samsung TV as a "go-to". But, you can find many alternatives.
From a driving perspective, ACC is probably the current champion on the console and if you are a SIM fan, this is for you. If arcade racing is your preference, you will find this game frustrating and getting banned from online lobbies more often than not. This game brings real life motor sport to your fingertips in the comfort of your own living space.
I recommend a SIM wheel set up over a gamepad to ensure you get the most out of the game. I use a Logitech G29 and I have no issues. The cool feature in ACC is that you can fine tune the wheel inputs to your liking (much like Codemasters F1). I have heard of wheel incompatibility on consoles, but have not experienced this for myself. It may require firmware updates on your peripherals as the game is "new". Patches will be released to fix issues as time goes on, so patience will pay off in the long run. Trust me, any bug fixes are worth the wait. For now though, we patiently wait for the GT4 cars to arrive on the console verson of ACC.
To sum up:
SIM physics: 5/5
Visuals: 3/5
Fun: 5/5
Content: 4/5 (fully licensed GT3 cars and tracks and GT4 on the way)