Last weekend, I put the bike on track for the first time, since I did this mode. Definitively an improvement to not think about them every time you lean, you just focus on your ride. However, I felt not perfectly comfortable to move my butt out of the seat, I couldn't open wide my leg to drag my knee down with the upper/forward position (I am 170cm, 5.5") I will move them backward and give it a try for the next time on track in october.
They still feel strong, but on the down side, the pegs are a bit narrow (especially the back brake), not as grippy as others, and you feel more vibrations at 8000rpm without the loads.
By the way, I am happy with them, they are not perfect, but having more clearance on track is definitively an improvement.