The Aleste 520EX is a russian clone of the Amstrad CPC and the MSX. It works not with AMSDOS but with the MSX DOS (see this russian site in english). There was already a thread about the Aleste 520EX on CPCWiki, but this time Sebastian Blanco is talking about the Aleste kit he just bought. Finally he isnt the only one in the Amstrad CPC community to have one. If you are interesting it's seems to possible to buy one kit by writing to tetroid at inbox ru like Sebastian did.
You can see a youtube video of an Aleste 520EX running the Phortem demo by Condense (and MSX games at the start of the video).
Une modified version of Caprice32 permits to emulate at least in part the Aleste 520EX.