The Harmony wheel is very similar to the original Premier wheel but made using black and white in stead of the original brown and dark brown. 57mm x 30mm

Fo-Mac wheels are retro-style wheels using a compression molding process.  The materials used are much different than urethane wheels of today.  The formulas used are unique and different from each other and can offer a different skating feel.  Many factors will contribute to the performance of a wheel like this; such as weight, floor material, temperature, etc. 

Hardest - Premier, Mini-Mac, Freestyle, Slick, Harmony
Hard - All Amarican Plus, All American Gold, All American Dream