The new Michelin Pilot Sport 4s is coming out early this year but apparently it has a higher silicon content so probably won`t be as good as the super sport that it is replacing.
Tyre choices seem to be getting worse not better 
We have tried the current PS4 against PSS on same car, and the PSS appear slightly better at cornering, and marginally more stable in a straight line.
I am currently running PS4 on the rear of both my Omegas.
I`d like to try the MPSS on the Z, it`s wearing Vredestein Ultrac Vorti`sat the moment but I don`t have anything to compare them with but I`m not too taken with them.
Given that it
appears they are slowly being withdrawn, I tried the PS4 in the hope that if they are any good, I might still be able to easily source them in 2 years time.
I won't pass too many comments on PS4 yet, as I have not used them over their entire life, and certainly PS2 and PS3 were great for the first third/half of the tyre, then went to a more slippery (but quite durable) tyre... ...much to Lazydocker's anguish as we drifted towards the side of a truck when he was helping calibrate the LPG one day

.