Here are the two fruits opened. The granadilla (orange-like one) has a very hard outer skin. You have to first poke it with the end of the knife before you can cut it open. Once you're through the outer skin it is easier to cut. The mamon (red-spiky one) can easily be broken in two with your fingers. The spikes are soft and not prickly. This is like what you would see on "Fear Factor" (which happens to still be on here). Now which one do you want to eat?