Depends on what part they will live in but most of Richardson is great. It just blends in with North Dallas, Plano and Frisco. Lot's of great shopping and restaurants. They will be fine and learn the lay of the land quickly. What are their ages? Young, Middle or old? I might be able to be more specific where to go.
I'm just up the road in Frisco, have several accounts I call on in Richardson.