Ive been skating the powerflex rockcandy gumball cores for about a month, the slide is nothing like f4s, its a lot grippier but i got used to that. The wheels feel very very hard and fast, the softer core makes it faster/smoother on rough ground (which i skate a lot). The wheels have a sharp lip which chips a little. Overall i like them a lot, but i might go back to f4s for the slide.