I know the opinions and prejudices (justified) that many of us have to rFactor, but there is a really interesting mod that made me completely change my mind.
I made this video to show you a few laps with a Lotus Exige S240 at Laguna Seca. Physics is very, very credible and there is a great natural feel driving. On this occasion I also used a mod that forces you to press the clutch otherwise the gears do not enter, and considering that you have to use the heel & toe technique to downshift properly, the immersion increases very much.
On the last lap (from minute 6:20 onwards) I tried to do some (small) drifts, to confirm that the car is controllable unlike many other mods where as soon as the rear becomes lighter inevitably goes into a spin ...
This mod, in my opinion, is very close to netKar. Indeed, in some aspects is even better (obligation to press the clutch and day night cycle). Enjoy!