Plex has long been a good alternative to Windows Media Center with its TV features being the only weakness, Plex are addressing with a new Plex DVR now in beta. Using SiliconDust’s HDHomeRun Plex can stream or record TV shows to its range of Plex apps including iOS, Windows, Android and the browser.
It has an EPG and supports a wide range of HDHomeRun tuners.
Plex makes it easy to discover new TV shows and helps you find things you might be interested in. With an intuitive, customizable program guide and powerful search, you’ll be able to easily find and record single episodes, entire series, news, documentaries, and sports. And all of your recordings will be integrated seamlessly with your existing media libraries, giving your DVR the full power of Plex!
Currently it is only available for Plex Pass subscribers and there is more information at Plex.
Also if you are looking for an alternative to Media Center checked Emby as well.