I do a lot of boondocking, and as such most of the time that the furnace is running is using precious battery power. And it is noisy. I would rather have a higher heat output for a very few minutes, then shut it off.
When not boondocking, I am in a campground with hookups, and then use a electric heater, and don't hear that fan at all!
Also when boondocking, my Olympic 6000 Btu catalytic heater is on if it is below 45F outside, and I don't cycle the furnace much, until below 25F outside.
So the two stage will not do me any good at all.
Fred.