I purchased Red Leghorn chicks from Murray McMurray last spring. Let me start off by saying I have ordered chicks from MM for years and their chicks are always hardy, vigorous, and we rarely experienced losses. That is, until we ordered the Red Leghorns. Out of the Red Leghorns that survived shipping (both the initial shipment, and the subsequent replacement shipment), I only ended up with 2 Red Leghorn males that survived. All of the pullets, and 2 of the cockerel chicks died. They seemed very tender and fragile. Not hardy and spunky like the White or Brown Leghorns in the same order, of which we did not lose any in shipping or in the days/weeks after they arrived that I recall. The Red Leghorn line must be weak from inbreeding, because a friend of mine ordered a very large shipment of 40 chicks back in the summer and I think he only has 6-7 chicks that survived out of the bunch.
That being said, I have ordered more chicks (not Red Leghorns) from MM since then and will continue to order chicks from them in the future. I don't hold the bad experience with the Red Leghorns against them. They swiftly tried to make it right with me and have wonderful customer service. I commend them for trying to offer such a rare variety, but like a lot of rare birds, due to a smaller gene pool, the line is not as sturdy and robust as breeds/varieties that are more common and less rare because of limited access to fresh breeders to add genetic diversity to their breeding stock.
We culled one of the Red Leghorn males due to wry tail and still have one of the males we are using to create my own line of Red Leghorns. I will dig through my phone to hunt pictures.
I highly recommend Murray McMurray as a hatchery, but I can't recommend ordering their Red Leghorn chicks unless you plan on picking them up and taking extra special care of them because they are delicate and tender when they are chicks. Their White Leghorns and Brown Leghorns are super sturdy and hardy as chicks, and survive well. They are healthy and lay well as they grow out. I highly recommend those two varieties, as I have personal experience with them. Our broilers from them also did very well. I also have Silver Leghorns from them, and they are also very hardy and robust. They are just on the dainty (small) side. lol
I hope this helps.