I have started using the PC connection instead of the hot shoe for flash. My impression so far is that using it bypasses all the restrictions the camera would otherwise apply to use of flash. The only restriction I have seen my use of the PC socket apply is that only Manual shutter will fire the flash, that makes sense. Therefore when using the PC socket the camera will not interfere with ISO setting nor prevent use of Constant Preview, nor control White Balance or other features. I appreciate the benefits for my use of off camera fill flash on the G9. Anyone else have experience with the PC socket?