At Sea level a 530F is not much if any faster than a D in cruise. The round nose is better aerodynamically and the extra 200 pounds or so makes a big difference.
My last cross country in a 500D I cruised in the high 130knot range at 70PSI all day long (with frequent fuel stops). If I wanted to push it to redline I believe I could have hit 156knot VNE in level flight