Rails sometimes ask for a non-refundable deposit, sometimes not. When they don;t you still have to go through the deposit payment ritual of paying them nothing in order to validate the credit card they will charge in due course (if it hasn't expired by then!)
From what I've seen the nil deposit is usually on models which are announced but the price is not yet fixed, although in this case they have been given an RRP. They generally include the option to pass on any increase in price if the manufacturer moves the goalposts, with your retaining the right to cancel in these circumstances and get your deposit back.