Could anyone tell me how old weimaraner pups need to be before their personality can be seen as we are to visit some pups soon to choose and im not sure if its too early?

I've never found that a pup's personality is really evident until they are about 6 weeks old.
:)

I would say after living with Weims and puppies. That the characters dont become evident until 7 weeks onwards. Then it very much depends. You cant see the true Weimaraner for what it is until 9 weeks upwards. I like to see a puppy as a mini adult. That may sounds odd but you can see the potentiol in a pup. If you want one to show then you can see at 7 weeks but the older the pup is the better.
If you want a working dog then choose one thats active.
What in particular are you looking for.
Have you seen a litter?
Nutkin