Agree on it being a bit of a mess. Endfield and Boyd as the the two main characters just don't sound right. It really seemed dumbed down - they kept on dropping hints as to how the whole thing works out.
I've got mp3s of both the Dirk Gently books read by Douglas Adams himself which are far far better (as well as Last Chance to See which is pretty good as well).
Did like the sounds the electric monk made though.