Re your paragraph, “You mention that once I place my order I have entered a contract, is this correct or is the formal contract in place once the vehicle is collected and my pin is submitted? Would I be able to cancel my order before it arrives should I find out (through a test drive or similar) that the grandland is not suitable for me?”
The order is placed with the Dealer as per the specification you require, and the Dealer then requests said vehicle from the Manufacturer.
When you enter the PIN, you have then accepted said vehicle to be acceptable; as being to specifications as ordered, but subject to any manufacturers change of specification between the two dates.
Having a disappointing test drive between the two dates is not a valid reason for cancelling an order. Likewise, neither is placing an order for a Qashqai, HS, Sportage and Grandland – then accepting the vehicle which turns up first. (Hypothetical scenario)