All just my personal opinion
Mahler: Symphony No.5 — comparing recordings with the following artists: Walter/NYPO (1947), Haitink/Concertgebouw (1970), Solti/Chicago SO (1970), Abravanel/Utah SO (1974), Sinopoli/Philharmonia (1985), Bernstein/VPO (1987), Abbado/BPO (1993), Zinman/TOZ (2007)
Beethoven: Symphony No.4 in B♭ major, op.60 — comparing recordings with the following artists: Bernstein/New York Philharmonic (1962), Bernstein/Vienna Philharmonic (1978), Böhm (1972), Dausgaard (2000), Furtwängler/Vienna Philharmonic (1953), Hogwood (1986), Klemperer (1957), Norrington/RSO Stuttgart (2002), Toscanini (1951), Walter/New York Philharmonic (1952), Walter/Columbia Symphony Orchestra (1961), Zinman (1998)
Gustav Mahler: Das Lied von der Erde — comparing recordings with the following artists: Walter/Ferrier/Patzak (1952) / Klemperer/Ludwig/Wunderlich (1966) / Bernstein/King/Fischer-Dieskau (1966)
Franz Schubert — Lieder, *not* recorded by Fischer-Dieskau: interpretations by Ferrier/Walter (1949), Wunderlich/Giesen (1965), Price/Sawallisch/Schöneberger (1981), Haefliger/Dähler (1987)