I Need A Bit Of Expert Help Switching To Android. HTC One, Z1 or Moto X?

I'm looking to make the switch from iOS to Android and I need to get a phone before the end of the month as I would be getting 40% off of my total contract price. The full list of phones I can choose between can be found here, however I think I've narrowed it down to these three.

Things that matter to me are hardware design, I want to to feel good and sturdy in the hand, a good camera, and ideally a relatively clean (not to bloated) version on Android (KitKat would be nice) however I'm considering Cyanogenmod'ing whatever I get anyway, if it needs it.

I'm leaning towards the Z1 and the HTC, I loved the look of the Moto X a few months ago, but the lack of Moto Maker here in the UK is a disappointment. I did consider the S4, but the hardware design leaves something to be desired. What do you lovely people recommend?

For context, the prices I would be paying per month for each are below.

HTC One (Unlimited, 5GB 4G Data): £27 (~$45)

Sony Z1 (Unlimited, 5GB 4G Data): £27 (~$45)

Moto X (Unlimited, 4GB 4G Data): £25 (~$42)