Do swept wings require more aileron differential for axial rolls?

I have 2 sets of wings for my Facet: one is straight with a tapered LE the other is swept and tapered. They have about the same amount of differential but the rolls with the swept wings aren't axial.

TIA

I'm guessing that it has far more to do with the CG shift than with the differential. By shifing the wing back you move the CG back too but no where near as much as it should be moved to keep it at the same location of the MAC.

BMatthews may have a point here. To make it more clear, sweeping the wings back effectively makes the plane's balance more nose heavy. This requires more up trim for level flight. This up trim gives you barrel rolls. Swept wings also have more yaw-roll coupling than straight wings have.

Look at the photo. The swept wing is located further forward at the root. It is entirely possible that the center of pressure is still appropriately located so that there is no need to shift the C-of-G.