N4 & Ordering on day one.

So I'm in the UK and I'm set on the nexus 4, looking to order as soon as I see a buy button, something on my mind which has been brought up is defective units, I'm too Impatient to wait a few months for possible defective devics to be rung out but how common are defective units or specifically with lg devices or previous nexus devices, also does the N4 have some sort of warranty if so for how long?