So I had the car at Laguna Seca with speeddistrict on Apr 5th. I ran it in the dry and also wet sessions. The front ducts worked exceptionally well. There was no pinging from the rotors and the amount of radiated heat was far less compared to my last Laguna outing. The rear ducts didn't work as well, as the rear rotors pinged quite a bit and felt much warmer compared to the fronts. I think some sort of inlet is required to improve the airflow.
As far as clearance goes, I did manage to tear the right front duct a bit. I think this was on turn 6 as it really compresses the car if you hit it just right.
Here is my run of 1:47.2