Unfortunatly I was only able to speak to four vets. This is what I found out:

2 of the vets neutered young, the other two didn't.
2 of the vets said that the hormones aren't needed.
1 of the vets said that they are needed for mental maturity.
And 1 of the vets said that a dog shouldn't be neutered until atleast 4 months because that is usually when the baby teeth fall out and a vet will pull out any baby teeth during the anesthesia for cheap.

I'm still doing my research, but there is still no adverse affects.

My vet would not alter Oz until he was at least 6 months old.
His reasoning being that those hormones are needed for
proper bone development. I also frequent several agility lists
and they have many discussions about not altering your pet
until the growth plates have closed for the same reasoning.
Logically speaking it does make sense to me. So before I
have my next dog fixed, I will be doing more research and talking
more throughly with my vet about it and if I feel like it's more
beneficial for the dog, to wait until a year or year and half before
fixing, then I will.
But some dogs' growth plates don't finish closing until 4 years old. I wouldn't think it right to wait that long...