Got it from post office yesterday. I am pretty impressed, it will take two Wansen WS-560 flashes and I am able to take photos with full flash power with about 1.5 s charge time. Flashes don't warm up like they do with their own batteries so I probably can take as many photos I like. Instructions say that you should take a break after 20 fast full power flashes. With 1/8 power I was able to take something like 15 photos in burst mode. The Wansen flashes had a loose pin in the outside power connector. I used epoxy (from inside) to fix them. It seems that my Godox ring flash has got some problems with high voltage circuit as it works ok with this unit but is unrealiable with its own batteries.