Well I have Falken FK452 on the front of my GT-R (old Potenza TS-02 on the rear, came with the wheels) in 265/35/18.
So my opinion (brand new tyres): FK452 > KU31 > 595 SS. The Federals were pretty decent when new (215/45/17) but about 50% worn and onwards they were shit (one year old). KU31s are heaps good throughout the life of the tyre. I also had Nexen N8000 (Ozzy tyres bait and switched me, but I was desperate hahaha, same price as KU31 though) on the front of my GT-R in 265/35/18. Grip about the same as KU31 when cold (dry), but overheated very quickly. Same grip level in the wet. Went bald really quickly (within 10,000 km), so I wouldn't bother with it, get KU31 or FK452 if you can find them cheap instead.
I have new Dunlop Sports Maxx in 235/45/17 and 245/45/17 for my R31 but haven't driven it yet as I need to roll the guards first. Will report back when that car is on the road again.
Potenza TS-02 are okay on the track, nothing special, it is a street tyre.