Is this the longest pressed CD yet?

[Eine Alpensinfonie]

They've made much shorter CD singles on normal 5" discs.

[Sir Velo]

One must be the Carlos Kleiber Brahms 4th symphony - around 40 minutes.

Surely, more a case of never mind the width; feel the quality?

[Eine Alpensinfonie]

In the Phase 4 box set, there's an even longer one:-
Bizet: Excerpts from "Carmen"
and as a filler: Tchaikovsky: Symphony no. 6.

Total timing: 84' 12"

Whether or not you can get quite so excited by the performances, with the RPO and Henry Lewis, is a different matter.