What are some alternatives?
When comparing Sonarr and Medusa - TV Library Manager, you can also consider the following products
Sick Beard - Sick Beard is a PVR for newsgroup users (with limited torrent support).
Radarr - A fork of Sonarr designed to work with Movies.
FlexGet - FlexGet is a multipurpose automation tool for all of your media
CouchPotato - Presently you can watch films and TV demonstrates in a flash by utilizing Couch Potato.
Novaroma - Auto Download Tv Shows, Movies and Subtitles.
TVShows - TVShows is a Mac OS X application that automatically downloads your favourite shows.