430EX with G1X?
Thanks for all the help. The idea of a 270 sounds good because of the size.
However, I do have a 430EX, but at first it would not work on the G1X. Hence the question. Following confirmation that it does work, I just fiddled with the flash, re-started the whole process, switching camera off as well, and then it was fine. I had already tried all that previously, but still could not get it to work at first. So probably some communication problem somewhere.