currently riding the famous mach 7. it rides pretty decent and there is no creases thus fare but I'm a little worried about its core. The mach 7 has a polyethylene core, which from what I've heard is not a great core material. anyways, what I'm trying to ask is that is it worth getting a new board with a polypropylene core instead? Will I notice a difference when riding? Is polypropylene better and if so how? Any feed back is appreciated.