I have a Citizen Eco-Drive Skyhawk. It's the model from a few years ago but has the atomic clock synchronisation feature. It was purchased for me as a gift from the US and I can tell you that the feature doesn't work here. I also tried to use it recently in London but it didn't seem to work there either. Heading to the US in a few months so fingers crossed. Regardless the watch is great 10/10.