Are myelin-sensitive maps interchangeable? We performed a scan-rescan study in 5 subjects using T1 mapping, magnetization transfer and myelin water fraction. We found overall that all metrics have high scan-rescan repeatability and that they are highly correlated with each other. However, isolating the main factor behind this shared variance is not straightforward because of the different interplays between the measures. In the end, what will matter is to what extent these relationships are preserved in the presence of pathology.