I've got a bitch (it was her first birthday at the weekend) and I can't remember my reasons why now but I was adamant when I got her that I wanted a bitch and not a dog.
In hindsight, although I wouldn't swap her for the world now, if I was going to do it again I think I would go for a dog, having to plan holidays and the such like around her seasons, I didn't really think about this at the time. And if I thought that by getting a bitch I would be spared the embarrasment of my dog trying to hump our guests then that would have been pointless because whenever anyone comes to visit no sooner have they sat down than she tries to hump their leg (I've done the birds and the bees talk with her but it hasn't made any difference)!
Whenever I've met other cockers, be them dogs or bitches, they have always had lovely tempraments and very waggly bums, not a lot of difference in size and always totally and utterly gorgeous.
I think if (or rather when) we increase our family we will go for a dog and get our bitch neutered.