There is no way to legally buy their ROMs anymore. You can only rent them in perpetuity. When they did sell them, they didn't forward port your purchases to their next device, which is hilariously stupid, and you know they'd take you to court for dumping those same ROMs to your PC to organize, customize, and play the way you like them. If they just sold these things DRM-free on a web site for me to put in Emulation Station, we wouldn't be having this discussion.