http://michigan.gov/documents/OWB_fact_sheet_3_reasons_11-10-05_142298_7.pdfDoes this smell of a little bias, or opinionated. Pretty strong statements called a fact sheet. It comes up whenever wood and boiler are in the search terms, along with OWB and a few other terms.
From what I have read, specifically a few in the city of Marquette ,MI are ones with an axe to grind against burning any wood. That city also banned snow machines for a few years, till the economic hurt they put on their own residents from tourists not visiting took its toll and they reversed the ban.
It does seem like its a small number of voices that squeak their wheels. You would almost think someone paid to have the letter published. I thought a govt agency isn't supposed to name brands and be impartial.
Although those are the brands and types of boilers I like and recommend. I would rather a consumer make their own choice from an educational and financial point.
I also wish Michigan and a few other states would have more incentives for these types of heating equipment. The east coast has $5000 incentives.