Olympus FL600 R flash usable on Panasonic G5?

Getting to know the G5, and feeling I need more flash for bigger groups and for a bit of reach -Panasonic is coming out with an updated model, the FL-360L, which looks for all the world exactly like the Olympus FL600 R... http://panasonic.net/avc/lumix/systemcamera/gms/gh3/body_expandability.html

Does anyone have experience using the Olympus FL600R on the G5 or other Panasonic cameras? The LED light would be helpful sometimes, and I know some of the other more advanced features will only work on the Olympus and maybe the GH3 (which it seems to be matched to), but they look like the same thing... and the older generation Olympus and Panasonic seem the same as well. And I will probably be getting a GH3 next year.

Asking because I'm leaving for an extended trip in early November and would like to take an external flash with me.

Thanks so much!

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Larry Becker