Hello all. GLoc RS-1 pads are the same compound as the 1521. They both take a bedding process, brake pads actually are designed to create friction on a this layer of pad material to work as designed, that is why there is a bedding process. The coefficient of friction of pad material and the iron treatment is lower than the pad material to pad material so folks have found these work better as the bed in.
Another point we have not covered is the importance of cleaning the rotors before installation. All high end rotors are shipped with a protective film on the iron that must be removed, old fashioned soap and hot water with a scrubby sponge is the best way to remove this film. It is possible to use brake cleaner to get this off, but not without scrubbing. The best indicator is that water ‘wets out’ rather than beading up on the surface. If the rotors are not this clean, it will greatly increase the length of time it takes to bed the pad material. If you are struggling with bedding, you can try cleaning the surface of the rotors with a clean scotch bite pad, both faces, and try bedding procedures again. After cleaning the surface of the rotor should no longer look shiny.