Do you have a link to the site?

This is a gas fireplace obviously?

I'd never heard of them, either, though it turns out that there's a couple dealers in my area.

They try and make a virtue of the fact that they release humidity into the home rather than outdoors, which probably depends on your area. Too much water vapor is usually listed as a negative on vent free FPs [the Mantis is vented, but the steam is captured and released indoors].

The flame looks more like a pellet burner than a regular wood or gas FP, and the unit looks is very similar to a pellet stove as well-- could probably pass for one if the interior used brick instead of logs.

Wouldn't make my short list if ambiance is the top priority, but it does have an open flame at numbers that seem comparable to an enclosed burner gas heater, and looks MUCH nicer than those.

Here is a link that might be useful: link

What they are doing with this stove is the same thing as a 90% efficent furnace. The condensate from the furnace is piped down the drain. On this stove it must be heated up again and evaporated into the room. I would imagine you can pipe this condensate to a drain in the house if you wanted to. It does not work on the same principle as a vent free fireplace, which exhausts its gases into the room loaded with moisture. this unit generates condensate which it adds back into the room air. Hopefully filtering it before they evaporate into the room air.

There is a thread on HVAC-Talk in the Fireplaces forum about this fireplace.

Here is a link that might be useful: HVAC Talk