I've mostly read about males growing bigger too, but in my first grow I had both females and males of different sizes, all were started at the same time. The two biggest ones (of equal height and shape) turned out to be female and male and they looked almost identical except for the preflowers. So don't be so quick to throw out any plants that grow like a monster and take forever to show sex, it's still a 50/50 chance.

Another characteristic I've read about, and noticed for myself about the males during veg, is they really smell like cannabis. The females had no distinctive odor.