I went round a showroom showing Jotul, Morso, and others, very pretty but they all had firebricks and or baffles, taking up internal space. Mainly because cast iron is not good material for a stove and needs protection - slower warm up and less thermal shock.
Puzzled as to why they do this but it became clear. First because cast iron is simply traditional and you get all sorts of nice shapes, smart designs, decorative patterns even. Also cheaper. Second they talk of them as "log burners" rather than mere wood burners, with a vague idea of having efficient slow burning logs on the go overnight etc.
Steel fabricated stove much less decorative detail or smooth lines possible but maintenance free - no new bricks, baffles, seals etc. Also the big advantage of fast burn - smaller stuff burns faster, hotter, cleaner (the rocket stove idea) and you can heat a room almost as quickly as a gas fire, with a few bits of cardboard and some scraps of pallet. But you can also do a longer burn with bigger stuff. Best of both worlds AND zero maintenance - but strange looking semi industrial appearance - which you soon get used to.