I tried to compile with the new development version. It takes 44 seconds for 4 pages of music for alto, double bass and piano. But there is two things to notice : 1- I am using JEdit with LilyPondTool, might add some seconds.
2- I ask for a MIDI file, which is the longest process of the piece compiling (about 20 seconds)
Without the MIDI file, the compiling time goes from 20 to 48 seconds (why such difference?)