What are some alternatives?
When comparing RapidComposer and Synfire, you can also consider the following products
Odesi - ODESI is a music sketchpad that exports your projects to Audio and MIDI.
Captain Chords - Write chord progressions in your favorite DAW
Helio Workstation - Cross-platform lightweight speed-painting tool for creating music.
Liquid Music - Powerful music composition plugin to help instantly produce original song ideas.
Harmony Improvisator - Harmony Improvisator is the most advanced harmonic composition tool on the market.
Orb Composer S - Orb is a music composition Artificial Intelligence.