I have used the KU36 's at barbagallo and found them ok, but not up to the semi R spec grip (Toyo 881 for comparison). They also wore down surprising quickly - front left had about 40% wear in 40-50 laps. Then went to the AHG track ans skid pan which is tighter and slower, but you get a lot of power down in second gear. Front left was below the wear indicators after a good hard afternoon. That's in a gen 1 crx with 160 whp and lsd.
I do support the view that you go out with road tyres. I did that first time, and it was worth it as you could directly compare road behaviour with track behaviour, and first time out you are not fast. It took me quite a while to get up to cornering speeds where I found the tyres going off in grip after 5 or 6 laps - about 6 times, to show the type of learning curves involved.
The advice given to me for the type of track work I do - essentially tuning days with lots of laps and the odd super sprint - was to get the cheapest semi R that were going at the time.
Hope this helps
