Long time reader, but newly registered. I need a small miracle. I have a standard size masonry fireplace that I would like to fit with an insert. My wife insists that the insert be able to operate for a few hours each night with the doors open. I am looking at the Lopi Declaration, but I really like the Vermont Castings Merrimack for the large viewing area. I'm open to other brands. Can many of these inserts be operated for a few hours with no smoke/overheating problems with the doors open if you have a screen in front of them and keep the fire small? I'd really appreciate any help. Thanks