We're replacing an older (1987) Rheem/Ruud Deluxe 90, and are wondering if a two-stage condensing furnace with multiple speed blower makes sense vs. a single stage 90+? Looking at Am. Std. Freedom 90's, and may well not own the home more than another two to three years.
As a percentage of total hardware cost, does the two-stage with four-speed blower payoff either in terms of $ savings on electricity, or a noticeable difference in improved comfort over a single stage?