The answer to this question is no.

Once you apply another transformation over a rotation you loose the rotation matrix.
I have just tested this in Illustrator. If you rotate a rectangle then the bounding box will alos reflect the items' rotation. If you save it to pdf without "Illustrator editing capabilities", when you load it again, the bounding box will be mapped with an identity matrix ( meaning that the rotation was lost ).

If you really want to do this, you can attach extra information to the item as you edit it ( store it's rotation, scaling, etc ) with the QGraphicsItem::setData function.

Regards