Some notes on the Atarimax 128 in 1: The file size limit for each slot is 32k, so the larger files don't work. They do work, I'm told, on the newer Atarimax "ultimate SD" version.
The "CoolCV" emulator includes SGM support, so the files do work there.
The SGM is an interesting add on. It adds much better sound and additional memory. I've always thought that if Coleco had never come out with the Adam and had stuck to video games, they would have survived the crash of 83. An enhanced Colecovision would have carried them into the next gen, as the hardware (Colecovision + SGM) is very similar to the capabilities of the NES and 7800.