I have the XperiaZ android phone and I love it. Water resistant, dust resistant, very tough screen and it's Telstra blue ticked for rural areas. It sat in the RAM mount to Maryborough and back through rain as well with no problems or issues. The voice quality is awesome and the screen is beautifully clear. I bought a Case Mate hard cover so the edges don't get scuffed or damaged. I have it bluetoothed to my Interphone F5 bluetooth on my helmet and the music is clear and phone calls at 100km/h work perfectly. The version of Jellybean that it's running seems very stable and so it has performed flawlessly. The battery life kicks arse and is way better than my previous smartphone.
All in all I'm totally pleased with it. The only thing that I would have liked is if it was a bit smaller, but I guess the pay off for the larger size is the HD screen.