React, the UI library by Facebook, is definitely a great tool for building User Interfaces. According to me one of the strengths of React is that it can be rendered on both client and server. You can create truly amazing isomorphic apps using React and Node.js. When users request a page they will get a server rendered version first. All the subsequent user interactions will use client side rendering. In this way you can use best of both the worlds. As your app can render server side the SEO issue is resolved. Furthermore your users also enjoy all the benefits of Single Page Apps as your app can render on client as well.