I think a lot of times it depends on the breed, but overall, I wouldn't say either gender is sweet or smarter than the other. I do prefer females though (in Tollers and Belgians, anyway), simply because they are smaller, aren't as heavy in coat, often seem more active/exuberant, like to be close to you but aren't as glued to your side as males, I prefer a more feminine look, etc. Of course, there are exceptions to everything I just listed. I highly doubt I'll ever have any more male dogs..though I've thought about getting a male Toller someday.