there is 1 thing samsung doesen't do, if you buy an samsung phone from USA then that phone will only work within USA so if you travel to Sweden or any EUrope country the risk is that phone wont recive any signal, thats because samsung doesen't use same type of antenna as Sony does. So sony is good since they use an antenna that supports all bands on D6603 so if you buy it in Europe it will work fine in china, Russia, USA and all other countries without any issues. Also it's not also due to antenna as well it's that Samsung made USA phones only working within USA while Europe models only work within Europe, while sony supports both.
I know this because where i practice there is 2 companies 1 pc repair side and other is phone repair side and some american person came to us asking why their samsung s4/s3 didnt recive any signal and we told them that samsung doesen't support European bands if it's bought in USA so yeah.
