Quote Originally Posted by been_1990 View Post
Why does it seem that QML is faster?
Because QtQuick is fine tuned to some specific use cases.
But when I use graphics view, updating items positions is so slow...
Because your code is not optimal.

I think using setPos() might be the culprit. Should I subclass QGraphicsSvgItem and use it's paint() to update it's position?
No, definitely not. That would break the whole architecture.