i use ebc green stuff with my truck over sized rotors with good results. i have not needed to replace my mtb pads yet so i cannot say for them. i think you should give them another chance as well. try what hank told you. i would still tend to believe they are quality pads. i am not saying you did anything wrong.
i would clean rotor and pads with brake cleaner and break them in and see how they are.
i would appreciate a follow-up post regarding whether or not the green pads work for you for my own future reference.
thanks