Hi,
There is generally no difference in intelligence between sexes. Males tend to mature later than females, so can appear to be less smart. Many people prefer bitches as they are seen to be more affectionate and loyal. I prefer bitches purely as they do mature earlier on the whole. But any other difference tends to be more of a difference on the handlers attitude to the dog.
Males tend to be a little more dominant than bitches but castration as and when the pup reaches emotional maturity and proper obedience and handling makes this a non issue. Saying that I have met a good few really hard bitches in my time! Bitches should be spayed after their first season.
Enjoy your puppy and good luck!