We had one for 9 years, top of the range mcz musa hydro. It was extremely efficient. We bought bags of pellets, cheaper by the tonne on a pallet. Our home was energy efficient and 4 beds only took 1.20 tonnes a year, for both central heating and winter hot water. Pellets are easily obtainable, bag weight is 15kg although 10kg bags can be had
It is a extremely efficient method of heating, something over 90%. No fumes and only a small handful of ash at each clean. It works very well as an inclusive in eco systems ie solar hot water, AV electricity etc
I am now widowed and have moved to underfloor gas ch and in all honesty, the downside of pellets became the storage and the sheer weight of lifting each bag into the hopper in the stove. The stove was very automated with timers and programmers and very reliable. You need to get a specialist service once a year and the cost of that ranges upwards from £160, if you can find someone who is a specialist
I now have a log fire plus gas, definitely not as efficient as the musa but so much easier for me