Arm/interarm molecular gas, SFR, and SFE contrast as a function of stellar mass contrast. The solid black line marks the 1:1 relationship. All radial datapoints are shown as open circles in the background. The coloured solid line indicates the best bisector fit to the coloured circles, which represent the average per spiral segment. The fits are provided in Table F.1, and we list the slope as m inside the plot. The strength of the correlation for the coloured circles is indicated by ρ.