What are the differences betwen InstallBuilder and InstallBuilder for QT?

BitRock InstallBuilder for QT includes the same features as regular InstallBuilder, but with the availability of an additional, Qt-based, GUI mode. The rest of GUI modes, such as GTK, X-Window, etc. are still available. This is, of course, completely independent of the look and feel or libraries of the application being packed. The addition of this new mode increases a bit the size of the generated installers, but has no impact on performance.