There are no 3 sheep burners period.
The 3 sheep (cd only) burner is an invention of alexnoe and no such burner has ever been made (though some of the very old scsi plex burners (cdr only) come close. The plex premium is a very good 2 sheep writer and handles all cd versions of safedisc up to v.2.8; for higher versions, it's hit or miss (i.e. some individual writers can cope without weak sector enhancement, some will succeed with weak sector enhancement, and some will fail altogether).
So far as dvds are concerned there aren't even any 1 sheep burners (i.e. no burner can write weak sectors accurately to a dvd.