I’ve had the privilege of owning the xperia Z ever since it came out, since it was basically the only waterproof phone out there at the time, and it also happened to be on my carrier, T-Mobile.
I remember my first week with it. It overheated quite easily, and soon, within the first year, the back plate started melting. You can read quite a lot about that problem on forums, and even worse sony didn’t warranty it. Overall, My expierence with it was more or less decent. One handed operation wasn’t easy, and now that I have the Moto X, I don’t even use it anymore. Sure the front and back glass feels and looks good, but it just doesnt give you the grip.