The Dreamcast Magazine for the UK has wrote a small article on Dreamcast emulation. This article discusses mostly about how they recieved a few cds with dreamcast emulators on them. It discusses some emulator called Sega MD which I believe is really SegaGEN but they decided to change the name. Unless, someone can verify SegaMD exists. They also talk negatives about emulation as a whole calling it piracy and such.
