Sorry, you asked earlier how quickly they can grow; when fully supported, I would expect a monthly growth increase between approx 5 to 8cm, their metabolism is at it`s highest.
By the way, they don`t need a full grown hen`s egg, that`s why the quail eggs/chicks are good, a nice size for them, offer them raw (the eggs), cooking will lose some of the nutritional value (still a decent meal, nontheless).