Few questions, is there a SBI for the latest Neo4All cd ? If not, can someone make one?

I tried this and it worked amazing, using Beta4. I love it. But I am curious, what is AES/MVS ? I understand it has something to do with those expensive cartridge versions, but is it using a ROM when you use AES/MVS? What is the difference between the files? I'm confused, please, someone fill me in. Thank you.