A friend and neighbor is finally going to go to wood----making a statement, he says, "for Global Warming". They already have made a partial move by buying a Rais stove ( very big $$$$ and not the best heater ), now it's to be a Tarm boiler. He says that the total cost will be close to $25,000. Sound about right ? The wood shed is being built next to the Tarm, insulated and heated ! Nice. What has your experience with the Tarm boilers been ? Efficient ? Clean ? Durable over multiple winters ? User friendly ? Any downsides besides cost ? Comparison to OWB's and wood stoves and other gasification boilers such as EKO ?