Not really that long but, indeed, rather dark. Much darker than the first Dirk Gently novel, and significantly less funny, but not without some very funny bits.
The electronic I Ching calculator was badly made. It had probably been manufactured in whichever of the South-East Asian countries was busy tooling up to do to South Korea what South Korea was busy doing to Japan. Glue technology had obviously not progressed in that country to the point where things could be successfully held together with it. Already the back had half fallen off and needed to be stuck back on with Sellotape.