I've got no derict experience of that product.
Thechnically the "float" refers to the disc being not fixed in a rigid fashion to the carrier to prevent a thinner disc braking surface from distorting under heat/load, the non rigid fixing alows this to happen without causing the surface to deform and so keeping the disc more dimensionally stable and tracking straighter as it goes through the caliper.
You may have to play with clearance settings to see if it's needed to deviate from std but I would expect the braking performance to be improved when cold and wet as the thinner disc should come into normal operating temp much easier.