Works a treat!
I have the feed set around 4-5 teeth, there's plenty of room for more input, but it doesn't need it. I don't have any way to know how much time it's on or off but it can't be on more than 2/3 the time (guessing!) Real nice and even too, there's always a little bit of heat trickling out of the vents with the blower off. The original "modulating/variable speed hi-efficiency furnace"
Stack temps (magnetic thermometer) running 170-200ish at full fire.
Had to speed up the blower when I tied it into the duct system, it wasn't moving enough air, and furnace was smelling 'hot'. Still need to check temp rise with duct tie in place; I suspect it's close enough, air at registers seems very similar to oil furnace output temp, maybe a little cooler.