What are some alternatives?
When comparing Rocksmith and Frets on Fire, you can also consider the following products
Clone Hero - Clone Hero is a free rhythm game, which can be played with any 5 or 6 button guitar controller...
StepMania - Rhythm game for Windows, Mac, and Linux.
Osu - Osu is Music, Rhythm, Single and Multiplayer video game developed by Dean Herbert.
Audiosurf - Audiosurf is a music-adapting puzzle racer where you use your own music to create your own experience.
Incredibox - Express your musicality, pump it up and chill
Rez Infinite - The ultimate version of Sega's psychodelic rail-shooter adventure Rez, fully remastered and evolved, including VR support and additional new content, all by members of the original development team.