Indoor rocket cook stove safety/practicality?

You know those basic cob rocket cook stoves people build in 3rd world places so they don't have to breathe the fumes from a smoldering fire indoors? (For example) Would something like that be up to snuff for our ideas of healthy living? How much ventilation would I need? And lastly, could it work as a mini mass heater if I just pack a bit more cob around it?

I'm thinking of putting one in my 6'x12' cabin to cook on and hopefully keep it above freezing inside for at least 8 hours in 0F weather. So far I've been just putting a hot water bottle in my sleeping bag to keep me from freezing to death, but I could do with an ounce more of comfort.

I know a legit RMH™ would be better. But I think it's overkill for my needs, takes up too much space, and costs more than my cheap butt is looking to spend while a cob one is free.

You can make a rocket mass heater entirely from cob. I once built a rocket cookstove with enclosed chimney suitable for venting outdoors, and that design could easily be modified to include some heated mass around the core without taking up much more space.

Innovative design there! How many times has it been fired?

You might like this one too that Alec Newland built in his Anglo-Saxon reenactment hut - A cob stove with rockety burn and an oven. It is based on Romano-british kilns and is moderately clean burning and pretty compact. Exhausts through a side wall. I really think you'd be unwise to vent inside unless you have no other option.

Loving this idea... and the eye candy.