Help anyone.. for years I have wondered why 9 volt batteries are so different about their prices.. Eveready bateries cost almost half of others like Duracell bateries.. I´ve been told that Duracells are better for active eq´s.. I always use those in my bass.. but I read somewhere that Eveready´s were the best for fx pedals... why?.. what´s the difference? I guess knowing would help me save some ca$h..