bones: loud, slippery, very hard, no flat-spots, little coning, durable
pfc: quieter, still slide great, lil softer imo, flat-spots, and coning, last less long
bones are just a different style wheel to me. pfc's are like spits and I feel like more people are used to skating that type of wheel. if you like to powerslides you'll have to rotate your wheel pretty soon after putting on your pfc's because the back two wheel will wear down a lot faster