This stove performs way better than you should think. Offcource flu gases dont come down towards the most effective larger masonry-stoves but it heats the room really well with going through less than a 1 kubik meter of wood in a month ! And the room temperature in the morning is just slightly colder and heats up quickly. Comfort and dryness of the room is very different than with a conventional stove. Total cost of the stove is around 65 AZN. That is less than 100 USD.  With the wood price here in Azerbaijan it pays back within one winter! Expected lifetime? Ill give it some decades with minor maintainance.