There's not enough information in the question to give a true answer. The reason there are so many breeds is that each one has developed in a certain environment, geographical area or for a specific purpose - meat, wool, beauty, hardiness, as terminal sires, to graze hillsides, all sorts of reasons, so there are now sheep available to fit every niche you can think of. For example, Soay will not give huge carcases, but they taste very special and can fetch a high price in certain restaurants. If you run them on very rich reseeded pastures they will scour horribly, but if you want a rough, rocky hillside grazed they will be great. They produce only tiny amounts of wool, but they can be roo'ed by hand and if left will shed their wool unaided - very useful in some circumstances. So it's horses for courses.