Take the Nürburgring 24h race as an example:
Every car used ABS in the 2011 race even in the highest classes. Manthey Racing Porsche 997 GT3 RSR finished 1st with ABS. Saying that switching the ABS off is more realistic is not necesseraly true. You would be suprised how many popular racing-series allow "helpers" like ABS.
I would keep ABS on 1 for the best overall performance.
Every car used ABS in the 2011 race even in the highest classes. Manthey Racing Porsche 997 GT3 RSR finished 1st with ABS. Saying that switching the ABS off is more realistic is not necesseraly true. You would be suprised how many popular racing-series allow "helpers" like ABS.
I would keep ABS on 1 for the best overall performance.