The 4 MB pre-merged Sonic 3 & Knuckles .bin is objectively better for playing, features, and bug fixes.
Below them, a single save prompt:
The game loaded not Angel Island Zone , but . The background was a dark, corrupted version of the Sonic 3 special stage—endless blue-and-white checkered tunnels, but twisted into spiral shapes. The music wasn’t the usual Sonic 3 jams. It was a low, humming version of the Sonic & Knuckles title theme, but slowed down 500%, with occasional piano notes that sounded like someone crying in the next room. sonicknuckleswsonic3 bin file better