I think I saw you. I was getting an iPhone too.
My experience: a bit crap TBH.
They had to search a bit to find a 32Gb, and I thought they were going to send me away, but one was found. It then took around 45mins to set up as there were problems with the O2 system.
Then the phone wouldn't set up right and we went through 4 macs to initialise. The WIFI looked a bit off in the store too. Trying to set the phone up was a pain. Finally with a new cable which they gave me it kicked in. Personally I'm still a bit unsure about the phone, as were the staff and I was told to "give it 24hrs". I think I should have been given a replacement on the spot rather than a Genius appointment on Sunday which I was given!
As an existing (non-iPhone) O2 customer, I didn't have to go through some of the hoops but I don't get a data plan for 24hrs. Not told this in the store. This again from O2 is sh*t and I should have been told as it would have saved me running back to the store after paying my parking fee.
So I'll be back to the store on Sunday.
Am currently having to restore the machine now. It's just not acting right. Looks like a lemon. Again, they should have replaced it on the spot in my opinion.
Not the Apple experience I expected.

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