Andy,
I took the following quote from this website under the heading "
Drawbacks:
http://bioenergy.ornl.gov/papers/miscanthus/miscanthus.html Miscanthus rhizomes have a low tolerance of frost. Care may be required in some locations to minimize frost damage, e.g. by growing a "cover-crop" over the winter, or by spreading a thick layer of straw in the fields.
Intrestingly Miscanthus is being cultivated as a bioenergy crop. Maybe only that particular strain is vulenerable to frost?
Anyway thanks for all the info! I think I'm going to use both, Bamboo & Miscanthus