THe published results of the LH long term trial are also a very interesting read... unfortunately only available in German:
http://aireg.de/images/downloads/Abschlussbericht_BurnFAIR.pdf
They report a 1% reduction in burn rate (due to the higher energy in the biomass fuel) and less wear on the fuel pumps.
The huge issue seems to be how to produce the biomass fuel and harmonize the sourcing and distribution.