When using fractional font sizes like 10.5, 11.5 etc the text gets elided even when not needed, the font size increases as well. I tracked it down to fontInfo not returning proper values on those controls. It seems that the control calculates the needed space with the proper font size and after that the text gets elided because it is rendered with a bigger font size.
It happens when A Text item is set on a Control.contentItem. Like used in the default RadioButton in QtQuick2.
I added a sample QML file which shows the issue.
Regards Usarin Heininga