Have the composer's works been favorably reviewed?
For reviews of recordings, scores or performances in review journals such and Fanfare, Grammophone, or journals focusing on contemporary classical compositions such as Tempo or Perspectives of New Music:
Music Periodicals Database (Full-text)
Covers many scholarly and popular music journals. Music Periodicals Database (Full-Text) indexes and provides full text for some, not all, journal articles cited.
RILM Abstracts of Music Literature (1967-) [Use your computer's find command to search "RILM"]
Covers many scholarly music journals and chapters of books. Provides an abstract of an article or chapter, not the full text.
Lexis-Nexis Academic
For performances reviewed in The New York Times or other prominent newspapers.