Pretty sure this hasn't been asked before; which watch have you no real interest in owning and if you did probably wouldn't wear it anyway, but would like to give it a try for a day?

Living large in a Jacob & Co?
Steven Tyler's diamond and leopard skin Daytona?
A half-a-million quids Patek annual calendar tourbillon répétition minutes?
A pink G-shock?

My choice would be a 47mm Panerai.