Your friend in the yellow I4 takes a better line through turns than that grey V6. It's also interesting that he's running in Tour mode, where the stability control is very invasive. They seem pretty evenly matched overall. That must have been with GGLC, I was going to go to that track day, but work got in the way, would have loved to check out the car.
Mechanical LSD's feel very different than ABS-based wheel braking, I wonder how that thing feels coming out of a turn.