basically bands that released consistently good albums before breaking up.
rules: Band needs at least 3 albums and if you'd rate at least one of their albums less than a 7/10, they're disqualified. Reunions count as well. Even if the band released a flawless string of albums, broke up, then reunited to release a duff album, they're disqualified.
The Velvet Underground (though this assumes Squeeze doesn't count (It shouldn't))