If you can afford A with all the extras its definately the one to go for. On a car like this you really need to know what you are getting. Say something goes wrong with B, clutch or something like that, and its not covered under warranty, how quickly can you burn that £14k? I bet pretty quickly looking at the prices you've quoted for other work! Defiantely see if the dealer can do the wheels and zorst at cost, hell, hes not making anything but hes still getting his sale.