Since Mozart's times, Piano Concertos have often been played in chamber versions. Mozart himself composed four Concerti to be eventually played with string quartet only. Today, playing Chopin's Concertos with string quintet (including double bass) is highly fashionable, and the two-piano version sometimes escape the prison of "educational arrangements" to land into concert halls.
Practicing Beethoven's Fifth Concerto, I thought about reworking it in a chamber music way. Nevertheless, the sound of the composition and the prevailing use of piano-wind combinations (woodwinds and horns) suggested a transcription for a quite different ensemble for the classical string quartet. The opportunity of playing with the brilliant ExclusIVe Quartet convinced me to try a version for saxophones: the extension is comparable to the strings, but the volume can be much bigger, and it's easier to recreate colors closer to the original (Saxophones are musical Zeligs...).
The solo part hasn't been touched, but the piano often plays along with the saxes in the long orchestral sections, to increase the orchestral feeling and fill the texture.