Buying a PS4/ iphone 5 in Hong Kong to use in UK?

I live in the UK but I will be in Hong Kong this august for a few days, and thinking it may be an opportunity to get a PS4 and iphone on the cheap to bring back. However I have a few questions if anyone can help:

-I understand that PS4 games are not region locked, so I assume I will not have any trouble playing games bought in England. However how does this affect things like PSN and blu ray? If I already have an english PSN can i still link it to the HK PS4?

-What is the current price buying a ps4 from somewhere like golden arcade? I know the retail for PS4 is around 3300 HK$ but not sure how much in a place like that

-Is this even a good idea, e.g not worth the trouble? Will I have trouble bringing it in a case back home for example?

- How much is an iphone 5 in HK and similarly is this not worth the risk for a hundred£ or so saving?

Any help much appreciated

Hi, I have lived in hk for a long time. I think it will be the same thing weather you buy from uk or hk, the price of the product will be same globally (if you buy from reliable store). Buy it from a good store like in a mall, will cost you the same. The main difference will be the warranty, and may be the language. I have bought the LG G2 from hk, and i'm using it in India, the only problem i'm facing is that i'm unable to purchase anything from the store. Since you are buying an iphone, i don't know if it will create a problem. I think you should check the price in UK, and when you go to HK check the price there. If there's a major difference and you are saving a lot, then you can but from there but buy on your own risk, because the quality of the product may be poor (may be duplicate), and also you won't get/use any warranty; if something doesn't work then you will have to pay for it and it will mean the same thing. IF there's not much difference then you should buy from UK, which will be much safer.