The tractor is a great idea-- they are never a quick moving bird, though they do stay mobile. I have four 9-month olds and they waddle very fast. They are bowling balls! Given their physical limitations to avoid predators, if you are able to maintain them in a tractor your losses might be less due to predation, or if you can supervise and protect them then a little while freeranging for an hour. Far easier to chop a few handfuls of grass with scissors than to let free range when only 5.That was my plan. To raise them separately. I have 14 egg layers, but will raise the meaties in their own tractor. I have read mixed reviews on them free ranging, but I am going to try that also.
Have fun, and enjoy the experience.