The four 24-bit 96-kHz remastered CDs I've tried, and been disappointed in, are:
(1) RCA: Gershwin, Rhapsody in Blue, An American in Paris, Piano Concerto, Variations on "I Go Rhythm"; Earl Wild, Arthur Fiedler, Boston Pops. Recorded 1959-1961. Remastering released 2001.
(2) Decca: Brahms, Piano Concerto No. 1; Clifford Curzon, George Szell, London SO. Recorded 1962 (by the great Kenneth Wilkinson). Remastering released 1999.
(3) Decca: Mendelssohn, Symphony No. 3 "Scotch" and Midsummer Night's Dream excerpts; Peter Maag, London SO. Recorded 1960 (Symphony, engineered by Wilkinson) and 1957. Remastering released 2000.
(4) Decca: Mahler, Das Lied von der Erde and 3 Ruckert Lieder; Kathleen Ferrier, Bruno Walter, Vienna Philharmonic. Recorded 1952. Remastering released 2000.
The RCA Gershwin is the worst-sounding one of the lot, but I'm not pleased with the sound of any of them. I buy a lot of classical CDs and I know from experience that remastering of analog "golden oldies" can be a hell of a lot better than this. RCA, for example, showed what it could do in some of the magnificent remasterings in their complete Rubinstein edition: some of these (e.g., the Brahms Piano Trios with Rubinstein, Szeryng, and Fournier) sound better than they ever did in their original release on LP. So what's going on here?