There are five different versions, varying in the amount of tracks and how said tracks were recorded.
Here is a list of what the different download descriptions mean:
- "Full" means that the entire soundtrack has been replaced with music from the prototype.
- "Lite" means that only the music that was fully replaced in the final is restored (AKA the PC Collection tracks).
- "Remastered" features tracks that have been tweaked to sound more polished, as well as having them sound similar to Sonic 3 A.I.R.'s remastered soundtrack.
- "Hardware" means that the audio was recorded from a real Genesis/Mega Drive.
- "VGM" means that the audio was recorded from a VGM player emulating the soundtrack.