It really all depends who you listen to. If you talk to your importer, they will give you copies of relevant documentation that says you can. If you talk to VOSA or DVLA, they will supply you with copies of documentation that says you cant. Go figure.
Having said that, the law DOES say that you can lgally drive an unregistered vehicle to an MOT test, OR a location where repairs for MOT are to be carried out.
Ive driven countless vehicles back from the docks and only ever had an issue once (and that was because he wasnt happy with the carlos fandango wheels sticking miles out the side of the truck
)