most of the riders skate stf the others like jimmy the greek and chris miller and kevin staab ride spf

ur welcome and i think stfs would be perfect for a concrete park since stfs are made for street type stuff which includes concrete but u cant go wrong with either set. the spfs are gripper for those masonite parks u can visit the bones.com site then click on why for a better explanation

Thanks for all the info. I've been skating SPF's and I think they're great on smooth concrete. I've been skating some rougher stuff and ordered some STF's and was wondering what everyone thought of the difference between the two while I wait for the wheels to show up. Was hoping for at least the same amount of grip on smooth concrete but can still roll around on the streets well. Not real pumped on sacrificing grip in the parks but I guess I'll know soon enough.