I have a friend who has a dog that the testees have not drop , I f they don't drop then it will more than likely cause cancer . So She was told they were best took out , it will cost that bit more as they have to open up to remove them, I think if you are not going to breed from the dog and you was planning on having them removed then there is no need to wait any longer but if you are planning on breeding then wait to see if they do drop.You need to weigh up the pros and cons on both sides , to me I think I would have him done as I would not like to think that my Dog would suffer with Cancer later on , Yes don't get me wrong some Animals will get Cancer what ever , but if I knew I could prevent it with removing them and had it done then I would , but you don't have it done and the possability is there that it could cause it then I would feel rotton to myself if he did.
Sorry if I havent helped and Im rambling on , but i thought I would put my feelings across,