The Jumbo is quite larger than the standard Pharoah or the XLD1. There are threads on BYC comparing weights. https://www.backyardchickens.com/forum/viewtopic.php?id=325114 Personally I have had cortunix quail since the 1970's. Just recently reaquired some. My birds are 7.2 ounces at 5 weeks. Will update at 8 weeks.