JMO, but I would be leery of a multifuel system. Like any other multipurpose item, it involves trade offs. Efficiency is probably not optimized for either fuel. I know the last time I considered a multifuel forced air furnace, which admittedly was a long time ago, it was cheaper to buy two furnaces & install them side by side. Plus if one had problems the other was ready to go. So I bought the solid fuel furnace & never bothered to replace the oil burner. There was simply no need. Again, it is just my opinion. Just carefully look at the numbers & space requirements then do what makes sense for you.