what happened to the Mirage 4000 and how good was it?

what happened to the Mirage 4000 that France produced in the 1980s? are any still flying as research aircraft or is the thing consigned to the history books? could France not have used the 4000 insted of the Rafale? how did the 4000 compare to the F-15 Eagle and Su-27 Flanker? has anyone got any good info or pictures of the Mirage 4000? it seemed a good airplane in its time.