I purchased 10 "Cornish X" from Tractor Supply. I lost one at 4 weeks, culled one at 5 weeks because it was dying and lost one at 5 weeks. I just butchered one yesterday at 7 weeks because he was having such a hard time walking that he was getting pushed away from the feeder. There was something wrong with at least one of his legs where it bowed in strangely. He'd be at the feed and shift his weight off the bad leg which would result in him turning about 60 degrees clockwise. He'd pick at the food over his shoulder and then shift his weight again which would cause hime to rotate another 60 degrees until his back was almost to the feeder and he'd look around for the food and flop around trying to turn himself around, sometimes using one wing to try to stabalize himself. It was really painful to watch and while he started off bigger than most of his flock mates, they were overtaking him and I figured it was better to just butcher him early. I will say that he had a very nice 4 lb, 6 oz carcass after butchering, so I'm looking forward to seeing how the remaining are at 8 weeks of age. I haven't been very enamoured with this breed, although I will say that we've had a extremely cold and snowy April and these birds are still in my garage. I had planned on moving them outside weeks ago but we've had nights as low as 7 degrees and snow every other day and I've been afraid to risk putting htem in a tractor. So, perhaps having the space and freedom to free range makes a difference in their health and mobility. I'll say "never again" to getting them this early and given the choice, would rather do the Freedom Rangers I raised last summer, but perhaps haven't given CX a fair chance but of the original 10, only 6 will make Sit to the full 8 weeks.