Red and Black Stars are a great for any purpose. Hens are excellent egg layers, only slowing down during cold weather. The roosters carry their weight by being fantastic dinner birds. Either males or females are easy to use for shows, but what makes them most useful is their function as a sex link breed, used to breed toward a specific quality you're looking for in a later generation.
Stars are an easy chicken to live with as they're friendly and dependable with their work. Being a sex link breed also makes them a little tougher than your average chicken, so they can tolerate quite a lot.
The Star's appearance is fairly standard with a small red comb atop the head, small red wattles, and red around the eyes. Tails are modest in stature with only a very small carriage. Red Star hens grow up to have a mostly red coloring while Black Star hens are, naturally, black. Red Star roosters are white with red and brown splotched in places while Black Star roosters look much more like the Barred Rock roosters.
Stars are on the simpler side of things with pretty much no special instructions beyond needing a chicken run, a coop, and some chicken feed. If you intend to use them for breeding, then you may want to look into specific types of coops, otherwise they're easy to take care of.