You'll find the S5 a very different but rewarding experience.
One other point to note is that if you buy from CPW you won't get an O2 locked and branded handset which means you will be able to use a non O2 sim card (when on holiday abroad for example) or at any other time when in the UK. Also, your phones software updates will come from Samsung directly rather than having to wait for O2 approval, which usually delays things for a month or so.
You can of course unlock an O2 phone but you will still be on O2 software even after unlocking.
I have no affiliation whatsoever with O2 or any subsidiary companies. Comments posted are entirely of my own opinion. This is not Customer Service so we are unable to help with account specific issues.
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