Never had personal experience but they have been around for years.. They do have some advantages over woodstoves but since they burn wood have alot of the same problems as wood plus a couple of unique ones.
The do take a long time to heat up to temperature I think I heard that it takes a day or even longer. By the same token if the place gets overheated you can't really turn them down. Wood smoke is a big polluter. In Jackson, Wy, 10 years ago they banned them in all new construction.
I see your point. They do need to be designed properly for the house they are going in and don't work great unless you have an open floor plan. They are much more efficient burners of wood, you would only need 1-2 cords for an average house and they don't need to be stocked in the middle of the night. And don't really produce that much smoke or leave much for ashes.
The real offenders are those crappy external wood fired furnaces!