If the "superinsulated" house is only 1160 sqft, then either the house isn't really superinsulated or, more likely, the heating load at design min temp is more likely much lower than that 35KBTU/hr. Calculating expected load for a truly superinsulated house requires more careful attention to detail than for a "code built" house. Shortcuts taken with canned software typically overestimate the load. My own house, a double-wall superinsulated structure, has almost 4000 sqft of conditioned space, and the best number I have for actual heating load is about 19 KBTU/hr, vs predicted 22, at a design delta T of 73 F. For your -45 C outside temp (-49 F) and 70 inside, your delta T would be 63% greater, but the house has only 30% of the floor area. Very crudely, I'd expect the heat loss for yours to be more like 1.63 times the square root of 0.3, or perhaps 90% of my 19 KBTU/hr, or perhaps 17. OK, if one floor, the exterior surface area for heat transfer relative to floor area, compared to my two floors, will be greater. Still, I have to think that 35K is too high. Make sure that 35K has been well done. If more careful calculations give a lower number, that will affect your choice of stove. Mine is a small Quadrafire Millenium 2100, with OAK. Its firing rate is advertised as 11-28 KBTU/hr, and that has worked well for us, and actually was used to heat the house by itself during the winter when interior work was being finished, burning just half time. We don't burn around the clock, though; it's just for perhaps six hours in the late day/evening. The house absorbs the heat comfortably, so we don't overheat.