OH SHIIIIIIIIIIIIIIIIIIIAAATTT...
I was going to ask, but you immediately provided info. Just released this past September? I'm sure that's one reason why I hadn't heard about it.
GT3 was the last GT I really liked. I tried to get into 5 and Sport, but couldn't do it. Never played 6 or 7. I've been all over the place with Forza Motorsport series. Loved 1, hated 2, didn't play 3, 4 is my favorite, hated 5, barely got to play 6, didn't get to play 7, and I've been hearing 8 is not great. I didn't care for the Forza Horizon series at first. I ended up having some fun with 4 and 5, but it wasn't what I was looking for in the end. Assetto Corsa, Project Cars, and various others couldn't command my attention. I still have fun with Dirt Rally 1.0 and 2.0, but overall, realistic-ish racing games just don't grab me like they used to. I wish I could use my Logitech G27 controller more, but I need a proper seat setup for it.
I loved GT1 and GT2 despite only playing both on emulator that was struggling to keep 15fps at the time. I skipped GT3 entirely since GT4 was already out by the time I managed to get a hold of a PS2 Slim. I never even had any other game for that console.
I was already working by the time GT5 came out so it was not a huge issue to get a PS. I was kind of middle of the road about it, didn't love it but didn't hate it either. However GT6 was a big big letdown. For me that's when the series really went downhill, GT6 lacked lots of features why I loved GT games, and is also missing half of the tracks from previous games. But at least it still had single player campaign unlike Sport at launch. I experienced Sport as an insult to all fans of GT. Although they added single player content to it in patches it never got a true Gran Turismo mode.
And finally GT7 was a total mess, which I experienced as even more of a let down since it was proof that the creators were now completely out of touch with what old time fans of the series wanted. It contained very little single player content at launch, all of it from the hand holding variety. And the physics were messed up too which they later improved in patches but not to my full satisfaction. Not to mention the ridiculously overpriced unattainable cars in it, which they said was to simulate their exclusiveness. But for crying out loud I play the game because those cars I'd never be able to even get close to IRL, let alone drive them. And now I can enjoy not driving them in a game too. Thank you. Geez. I sold my PS4 Pro and my copy of GT7 soon after it came out, and vowed I'm done with the series unless it comes to PC. To this day I consider GT4 to be the best of the series: GT4 -> GT2 -> GT5 -> GT1 -> GT6 -> GT7 -> Sport If I took the release pre-patches version of GT7 then it would flip places even with Sport. I'm not ranking GT3 as I've never played it properly.
I am not a Forza Motorsport Fan to put it mildly, only tried one or two and always found the physics to be really weird and unrealistic. Not arcade unrealistic but outright unpredictable unrealistic which is the worst IMO. On the other hand I did enjoy FH4 which should be the more arcade game, it actually had better physics than motorsport. I just found it to be ridiculously short and the map too small.
My favorite realistic racing game on PC currently is Project Cars 2, it has the right variety of tracks and cars. For rallying still RBR reigns king, but I have not played it for at least 15 years.
I have a whole bunch of PCSX2 testing I need to do at some point, so I guess I'll throw this GT4 Spec II onto the list, and give it a whirl.
PCSX2 works out of the box now, well except you still need a PS2 ROM to use it, but aside from that setting it up is pretty straightforward.
Getting the mod to work however is an entirely other case as it is a patch that needs to be applied to the ISO of GT4 with a special patching tool which you need to download separately. And the ISO can't be any random GT4 rip either it needs to be of a special beta test version, which you need to acquire. Here is the official page of the mod:
https://www.theadmiester.co.uk/specii/ Good luck.