On my race car I've used khumo V710's which are very very good,have a set of R888 which suck in comparison for autox.I went to a track day with the R888's,which is what they were bought for,and wasn't all that happy as the tire(full trad depth,hate to shave away a brand new tire)felt really squirmy.
I did also use a set of michelin race slicks,they were used when I got and they were surprisingly grippy and lasted well.