The main difference, as I see it, between MM and Sandhill is that MM is a LARGE production hatchery that pumps out thousands of birds a week. They do not particularly select for specific characteristics nor are they as concerned with preservation of genetic diversity as Sandhill is. Sandhill is a small family outfit and is very concerned with preserving genetic diversity and selecting for qualities that represent the breed. If you read down through the breeds they offer you will see notes on what they are selecting for in some of their breeds. They also give wonderful descriptions of the characteristics of their birds. They offer some varieties that MM does not carry such as the Blue Orpingtons (like Speckled Hen has) that I am just dying to have. I also want some of their other lovely birds, but have to wait until I have a suitable place. Hopefully in the spring. They do only have straight run birds. I for one am glad. They are not throwing away excess cockerals. The folks that get them can choose to rehome them or eat them or use them for breeding. HTH.