I bought the GP5 set in taupe last year.  Looks great and solidly constructed with nice heft.  Set worked well for a few months; after that, frequently used pans were no longer non-stick.  I followed all care and cleaning instructions and always cooked with olive or avocado oil (never sprays), so really disappointed with how quickly the surface seem to lose it's non-stick nature.   I have since purchased a Made-In non-stick pan that's become my daily work horse and have enjoyed it's durability in comparison to the the GreenPan GP5.