Do you have gmail accounts currently? I've heard of issues in the past where the accounts are registered in one country, but the device is in another. There are some regional restrictions put on apps/games/movies etc so some stuff might not work.
You get the Play store and contents for the country you're actually in. I was using a device bought in Mainland China, but when I went to the UK, I was getting the UK Play store, same thing in HK as well.
If there's any stuff that's subject to geographic restrictions, like Google Music(US only), as well as e-books, magazines and some apps, you're not going to have access to them. e.g. if you're in France, you'll get the Play store and Google services for France, and it will all be in French. We've had posts along these lines before about Play.
I have tried to use a VPN to get around it, but according to Play I had "
China Mobile Samsung i8552" that kind of gives the game away.
Apple on the other hand, doesn't do that, they base it on your registered address and credit card information. So I could still get full access to the iTunes Store for the UK, even though I'm in mainland China.
Samsung Apps seems to be different again. they apparently base it on where the phone was purchased and the account created. So I'm seeing Samsung Apps for Hong Kong, and can't see any way of changing it.