OK, had a gentleman come out yesterday to check things out and give me a bid. Seemed pretty knowledgeable and cleared up alot of confusion I had on terminology.
Stove Insert: Basically a wood stove, designed to fit INSIDE an existing fireplace. Generally designed for masonry fireplaces, pretty limited selection on which of these will work if you have a pre-fab framed-in fireplace.
Hearth Stove: Also basically a wood stove, designed to sit on the hearth of an existing fireplace, and vent through existing chimney. Can work with masonry and most framed-in fireplaces.
EPA Fireplace: It's a fireplace, just designed to be used as a heat source rather than "ambiance."
I guess now I need to call back the other folks I spoke to before, when I told them I was interested in a "stove insert" and described my current setup, most of them sortof poo-poo'd the idea and didn't think I would be able to get a very large unit. What I really want is a complete tear-out of what's in there, and replace with something more efficient, I think if I made the same calls again and used different terminology I would get much different answers.
Anyway the gentleman that came out offered a couple options, one being a
Regency hearth stove that puts out 70,000BTU's, roughly $3,800 installed, but it is fugly IMO. With that scenario the existing fireplace & blower vents stay there, and I have to figure out some way to cover/close up the area, I just can't visualize it in my head without looking all cobbled-up. I'm usually more of a function-over-form kindof guy but I do have some limits!
Second option was a (broken link removed to http://www.kozyheat.com/products/woodburning/z42/index.html) fireplace, rated 60,000BTU/hr and would require of course complete tearing out the old one, probably redoing the hearth, maybe even redoing the mantel as well since the new fireplace is taller and I may have clearance issues. Installed cost was right at $5,000, but does not include any masonry work to pretty things back up after the new fireplace is in. Can't imagine that would run much more than $500 or so. This one has the largest firebox of all of them and accepts 22" logs, which I presume would equate to a longer burn time, but I can't find any numbers for burn time on Kozy's website.
Third option same as above, except with a slightly larger Regency fireplace, I think
this one but I can't remember for sure, rated 70,000 BTU and a little nicer looking with arched doorways. He said about $1,000 more installed than the Kozi. Don't think the extra $1,000 is worth it for another 10k btu's.
We talked quite a bit and I learned alot. The hardest part about my decision making has been how fireplaces/stoves are rated. It's like comparing apples to oranges with each manufacturer. I see 70,000BTU and 1,800 sqft with one manufacturer and 60,000BTU for 2,500sqft with another. I've decided I really don't care what square footage the stove is "rated" for I'm looking for BTU values only. But even that isn't always clear either. Most list "Maximum" btu and others list BTU/hour which is generally a much lower number. Not sure which one is more meaningful.