This is usually the second question you are asked by the breeders you speak too. Both males and females are equally affectionate but some people do not want to be bothered with a females seasons.

Similarly males do like to mark their territory, even though it maybe in doors so you will have to be persistent with toilet training.

Some people say that a spayed bitch then gets too much coat and becomes fat. So it is a pity to buy a bitch and then have her spayed just because of a little inconvenience with her half yearly season.

There are advantages and disadvantages in both but you will usually find there are more male puppies available as breeders tend to keep their females to breed from.