GT1 Vett tires - Pirelli, Dunlop and Michelin question

I need some help here and for Endurance Series manual doesn't have information on that I was wondering if some of you guys could help me understand this.

As we know the GT1 Corvette has cars with 3 different tire suppliers in Endurance Series Michelin Pirelli and Dunlop are they all same? Do they all perform equally in game or different supplier make the car react differently?

Could some one from EnduRacers explain the main difference among these tires?
Thanks!

The changes are only graphical, the 3 tyres have the same physics.