I'm used to the 2016 Audi R18 on most circuit events that arent soley based on power... in that case I use the McLaren Ultimate.
I feel like the R18 is even more driveable than the Porsche 919 (I dont have this car). I got the Audi for free and I just use what I have.
The diesel 4.0 v6 really seems to have the torque to make things an easy drive.