DONIZETTI: "L'ELISIR D'AMORE." Joan Sutherland, Luciano Pavarotti, Dominic Cossa, Spiro Malas, singers; Ambrosian Opera Chorus and English Chamber Orchestra conducted by Richard Bonynge. London 414 461-2 (two compact discs). Despite a handful of major reservations, this remains the performance of choice for Donizetti's rustic comedy on CD for the moment. The 1971 analog original scored highest for the refulgent vocalism of its stellar principals rather than for any particular glint of theatrical individuality. Sutherland still mashes consonants gloriously, even if Adina's line hold no terror for her. Bonynge demonstrates a thorough knowledge of bel canto style at the expense of dramatic vibrancy, and the two supporting men are forgettable. London accommodates 130 minutes of music on two CDs, but the engineers have not modified the metallic sound of the original LPs.