The Dunsley neutraliser is just that - a neutral point.
We have a thermal store, which is a similar 'neutral' idea, into which goes a gas combi boiler (direct), and a woodburning stove (indirect, via a bottom coil, a supposed nominal 10kw to water, 5kw to room).
(We also have a solar upper/middle coil on the store for summer hot water... to be continued...eventually)
Off that store come the pumped and sealed system rads (direct) and ufh (direct).
There is a plate heat exchanger a damn sight bigger than the average combis, with flow switch and shunt pump for the hot water. It'll run two half-decent showers at once, when the store's fully charged.
The actual hot water side of the combi is rarely used, although the system is valved to allow hot water supply from either the store or the combi if the shunt pump were to fail. Works well although the stove does use a lot of wood, it will keep up with rads and supply a bit of hot water, unless absolutely freezing outside, then to be fair it can struggle keeping the house warm enough - then we light a smaller non-boiler stove. Or use the gas
An important bit is keeping the wood boiler at the right temperature to burn well - we have a laddomat loading valve that only lets out surplus heat to the store, maintaining the boiler temp at an efficient 78 degrees. Without something along these lines you'll get tarring of the stove and flue, poor burning, more smoke and less heat.
Navitron forum is a good place to start for all this.
It's all major effort - you really need to be aware of the work involved - the stove brochures don't show the mess, the dust, the backache, the woodstore, the log splitter, the state of the car when I've scrounged some wood from somewhere etc etc. I'll use gas every morning, then switch to wood if I'm around all day to run it, using wood most evenings during the winter. Excluding installation costs
it has saved money, purely because so far I haven't paid for any wood, but it's more about the warmth and the FIRE. We can get up to a good 30 degrees in our kitchen and an easy 21 around the rest of the house, all for free unless it's below zero outside.