RXB is nice, but I don't have an RXB cartridge, and I also don't always need all the extra features, and there is no way I know of to load RXB in RAM. I was just looking for a way to have a resident dir or cat command with XB that I could load from disk. There is some software I have that is called Disk Manager IV from Quality 99 software that does exactly what I want, but even though I have a working image in PC99 format, it is copy protected and I can't seem to figure out a way to get it back on a physical disk, so now I can only use it with emulation.
One day I would like to get an RXB cartridge though, too.