I agree with 427sharpe. I would only used forged. Hypereutectic refers to a point in the metal phase diagram when creating forms of steels. As you know, steel has different forms...martensite, austenite, etc. If you plot all of these on a graph and show where they fall vs. heating and annealing, etc...you can see the differences. The hypereutectic point refers to the point where you get a carbon shift. Hypereutectic refers to a steel with more than .6% carbon in it than the other forms.
Now, there are probably a million arguments to which is better or when you should use which. My dad's 1997 Mustang Cobra has hypereutectic pistons in it, and it's a stoutly build motor....6-bolts mains, piston
oil squirters, etc.
However, I would always choose forged. It's kinda like the thoughts you get in the back of your mind when someone asks you whether you'd rather have a cast or a forged crank....Forged all the way baby.