I am curious as well how these compare to similar irons. I want to know how they compare to MP54's. I am also curious as to how that test drive works through Bridgestone. I started a thread about the Bridgestone test drive program but am seeing no help. These irons have peaked my interest.
To me, the main differences were visual and in how turf interaction was. The 54s look thicker and have more offset, although IIRC heel toe length was similar. The DPC sole grinds worked better for me than the 54s, which played like they had more effective bounce. I think overall forgiveness is pretty close between the two.