I’ve found that the Price Per field in the supplier price list->Parts->Price Breaks is always /1 regardless of the setting at Parts->Detail.
Per the field help:
Displays the measurement unit for which the effective price displayed in the Effective Price field is being expressed. This is the value selected in the Price Per field in the Parts - Detail sheet.
We’re on version 10.1.500.13. Anyone able to test if this is working on other versions for me?