Should i buy an iphone 5 or xperia z ultra now? - 2

My birthday is next week and I was thinking of The iPhone 5 or xperia z ultra, I'm used to huge phones (I currently have Galaxy Note N7000). Don't suggest, Galaxy S4 or LG Phones as I prefer high quality phones over plastic phones. I don't care how much power is there in Galaxy S4, my girlfriend just got it and it has lagged atleast 5 times in the 4-5 hours I have used it. Basically, as the next iphone should launch pretty soon, should I go for xperia z ultrat? But, wouldnt it be very huge. Also, wouldnt the next iPhone be almost identical to this one.

Additional Details
Also, if it helps, I have an iPad 4th Generation and Alienware M15X. No Macbooks or Macs as I prefer Windows due to the fact that almost my whole life I have used windows 98, xp, vista and 7. I did use one macbook pro when I was studying in MIT(around end 2010), but I switched back to windows almost two - three months later.

It all boils down to your preference. But I would choose an iphone 5. I'm not saying xperia z ultra is bad either. Either one is worth having and I won't complain about it either. But if I had a choice I would get the iphone 5. Just because they last! And I mean last! I still have all my iphone's from 3g till the 5. Lol and its still kicking and working. And thats saying something coz new stuff with me don't last. As well as they should but this iphones they survive my onslaught…

Hope this helps a bit…

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