Cadillac ATS-V (Alpha chassis cousin to the Gen6 Camaro)
Proxes R 295/30R18 rears, mounted per Toyo's instructions, after six 25-30min sessions at NCM (two sessions mounted 'proper' direction, sat a month, four sessions rotated to opposite side).
I was running 29psi cold and targeting 34psi hot. Unlike 71RS in the same sizing at same pressures, the ProxesR were kinda oversteery, with the rears definitely slipping more. Pace has been comparable to the 71RS (low-mid 2:19s at NCM with my driving ability), though the ProxesR can make 1-2 more back-to-back laps at speed.
I'm told "don't fear the splice" from those who have used the RR, NT01 and RT660 so I plan to continue running this set but will rotate them side-to-side next outing.