Well, I am going to advise you over here in moving forward with Note 3 because I am not really a fan of Sony Xperia devices
But anyways deciding anything between Note 3 and Z2 is tough at all because both of the devices are good with everything !!! If I talk about the storage then I would say Note 3 comes with 64GB of internal storage while Z2 comes with 16GB of internal storage. So, at the end of day I am always been looking onto the storage then if you ask me then I would be choosing Note 3.
Rest I would leave the choosing thing upto you !!! 
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