hahahahaha buff core is how the core is machined it has nothing to do with the speed
long story short
Sliders=SLOW
Grippers=FAST
Why do you think every sig wheel is a gripper??? haha
it may have a demonstrable effect, what im pointing out that it is the only major physical difference comparing to the rest. if you know how they are shaped and you might consider that the concave can make the kinetic energy bounce in other directions other than straight back to the surface of the wheels and the ground, thus wasted energy.
in the difference in alu core and pu hardness it will always negate some of that energy poorly unless by some miracle we can negate the difference by changing sizes, stiffness and shape of cores and again the same for the pu. this will vary from surface to surface ridden upon.
if you can picture how light goes thru a magnify glass, the point of focus of the beam which has the most energy in that point is the point of efficient use of energy.
stupidly complex to some considering the purpose but you should know if you dont, i want go there. why cant we go that far? do we want to? its not a need but it sure is fun to dream of complexity usually saved for situations and purposes unjustifiable to many others