An old title perhaps, and in places showing its age, but full of features, and full of enjoyment, GTR2 is well worth a look - especially as it's now in the bargain basement bin on Steam.
The first thing that strikes you as you're rolling out of the garage, whatever the car you're in, is that GTR2 is old school. There's no grind here, at least in the sense of unlocking cars, tracks or upgrades. Whatever grind there is can simply be described as learning to drive the cars, and learning the tracks.
Here you get to choose your tyre compound, as well as making all manner of adjustments to the car. And those wet weather tyres have a purpose - it does rain in GTR2.
The comparison with iRacing is inevitable. Here is a ten year old title that has the aforementioned features. It might not look as good as iRacing, but that's not exactly state of the art, either. And rolling out of the garage feels so much better than spawning in pit lane.
The AI is daunting. The minimum setting is 100% difficulty, you can only go higher than that. And it is a fearsome prospect to hear the AI closing the distance behind you. It will catch you and seize upon any opportunity to pass.
Race setup is flexible, with many options available with regard to session types as well as weather.
At the moment I'm having more fun with this than iRacing. Perhaps that's at least partly because I'm in my own sandpit. There is no external pressure. But so far it's been a great experience, and one I'm sure to take a great deal from when it's time to return to the more competitive arena of iRacing.