The reason you read bad reviews is because Dunkirk boilers are not particularly efficient when used for forced how water systems, however the needs of a steam boiler are somewhat different than for hydronic heating. Steam boilers need to be larger and have enough space over the water line to produce a good head of steam. Low mass boilers tend to surge and short cycle excessively. In your case the Dunkirk or a large Burnham or Peerless or HB Smith 8 series will produce the desired results. Try here www.heatinghelp.com and find the section called "the wall" There are a lot of old wet head's like me on there to give you advice. If I was installing for you I would be pushing Peerless but that may be a regional thing.