Just to clarify again-- the Sportrac 5 is a summer tire and the Quatrac 5 is an all-season tire. They are similar in that they are both round and black, and are made of synthetic rubber.
There are lots and lots of all-season tires of many brands to choose from, and I can't speak to the superiority of Vredestein's all season tires over anybody else's.
What I can say without reservation is that a summer tire is superior in nearly every way to an all-season tire for use in a sportscar.