Our largest corns have almost always been males, but there are definitely some big females out there too. There are not the consistent differences in size between males and females that there tend to be with boids - where females are quite consistently larger.
Nice thing about males is that you never have to content with egg binding - and we have had, or known about several young females that have never been bred that ended up egg bound. We recommend that pet buyers who purchase from us consider getting a male for that reason. It is really difficult to deal with a young, egg bound female and I would rather have pet owners avoid that if possible.
mary v.