I went with the Note 3 in the end. We'll see if I can even carry it. It was on preorder and doesn't even ship until tomorrow. Wheeee!
And now, to upset the North Americans, this is my plan:
-Totally unlimited data (no fair use policy)
-200 minutes (remember all incoming is free)
£12.50/month (and that includes all tax and fees)
No contract, just a monthly bill.