If you compare Swing toolbars (say SwingSet2) and native toolbars, there's a difference in a couple of things.
1) The header style does not match native (smaller)
This visual difference is a fidelity issue.
2) The toolbar does not stay active with the main window like native
This prevents tooltips from being shown, since Swing doesn't show tooltips on inactive windows.
To fix this, we require support from AWT.