Great combination. Did not have any trouble with MP37 3 and 4 irons, but I have not really missed a shot with the MX 23's. All are shafted with project X 6.5. Excellent trajectory. Much lower ballflight than when they came with DG S300. Before this set, I played MP33's. Excellent forgiving blade but I hit them way to high. They have a much lower COG than the MP37's.