A real-world test case is the Qt Creator's qml designer module.

1. Open any qml file in the designer
2. Select any item
3. Zoom in and notice that the resize handles have a larger "hitbox" than their graphical size.
4. Zoom out and notice that the resize handles are very difficult to click (since their hitbox is now smaller).

In essence, QGraphicsScene::items treats these items as transformed.

I've added some debugging code in FormEditorScene::mouseMoveEvent, and I've found that when zoomed in,

items(event->scenePos())[0]>contains(event>scenePos())

returns false.

Everything works consistently (but not in a useful way) when I remove the ItemIgnoresTransformations flag from the resize handles.