The whites look so cool, wish I could grow them but I don't want to stuff around with permitting and inspections etc.

Anyway, with the blues, the males are definitely bigger/faster growing and that is made even more extreme in tanks with mixed gender where the fish have access to the bottom for breeding. In cages at least the females keep eating instead of holding eggs.

I can't say much for the whites specifically as I only have experience with blues and catfish.

-on a side note-
I've actually decided that channel catfish grow just as fast if not faster in my system since the catfish keep eating and growing at lower temperatures and happily handle water just as warm as the tilapia. Only requirement is keep the water quality good and air up for the catfish but I've found that the tilapia don't eat or grow much if water quality is bad, they simply survive it. The catfish will start showing signs of illness with stress/poor water quality.