I've been experimenting with QtSvgDialGauge in a personal project, and so far, I like it a lot! :)
For those who don't know, QtSvgDialGauge is nice SVG-based dial/gauge widget, which is part of the Qt Embedded Widget demos. You can see it (and several other embedded widgets) in action in the Qt Embedded Widgets Catalog and Qt Patient Care Demo applications. And you can download the source for both applications here.