Can confirm the lag issue. Running 3930K + 7970 Matrix here and had most settings turned to max + 2560x1440. Were getting around 60-70 constant fps and game felt always little sluggish and controls were somewhat unresponsive. Well not as "realtime smooth" as LFS's for example..
Tried to figure out what was the issue here for all week long.. Just blindly trusted 70 fps being enough right?
This morning's tests:
40 fps range: totally unplayable, huge input lag and game felt like slug trying to get out from slime!
60-70 fps range: still sluggish, half of input lag what 40 fps had.. whole game felt sluggish, but so little that couldn't figure the issue
200-300 fps range: LFS-like responsive controls, cars feel alive, ffb isn't numb anymore, whole game engine woke up
Not sure if it's just AMD-issue here or what, but never seen that huge input lag before. Even Pcars at 50fps is totally smooth.
Also it has been years since saw last time this huge performance impact from AF.. AF turned off = 230 fps (KTM+Magione at pits) while AF 16x = 140fps