Don't buy watches for investment. If you buy a Rolex because you want to sell it, that means you hate the watch. When I buy a watch, I'm keeping it till the day I die. If I decide to sell it, its because I find it as a piece of crap watch. Why would you want to buy a watch, Rolex or anything else, to just sell it? Would you do the same with your wife?
Anyways good choice on the Green Hulk.