Actually, they don't all list the expected number nor size of the eggs. Privetts for example, lists good, better, etc and I engaged in a dialog with them to try to get integers out of them (range of number of eggs per year) and they said it was just a ranking, excellent is better than good, etc...
Why "avoid hoover's"?? They're one of the few who actually give you a number of eggs to expect per year, and the size of the eggs. I've never had any problems with their shipping or their birds.