Should we go with a small stove tucked inside a fireplace opening?

Hi Mike/Liza,
I had a very small opening as well, and was able to get a small insert in the fireplace opening.
What is the front to back measurement? And do the sides of the fireplace slope inwards towards the rear? (Edit, duh...haven't had my coffee yet...of course it tapers to the rear Also, what is the measurement from the bottom to the top of the opeing?
Basically, a good idea would be to take a big piece of cardboard and cut it to fit the exact bottom of the fireplace...leave about 1/4 inch all around for a little wiggle room.
I think its going to be tough to find one that fits....my answer insert I think is 23 inches across, so if yours tapers front to back that one would even been too small.
An idea might would be to go with a stove vs an insert.....there are a few out there that have a short leg kit...Jotul 3cb I think, and perhaps others.
By putting a stove in, you may have to extend your hearth a bit as normally you will need 18inches of clearance from the glass on the door to the end of the hearth.
Pro's of having a stove is that it would extend out of your hearth a bit, and you would not not need a blower for it....which is handy if the power goes out....also, I think the Jotul 3cb can either be a top vent or rear vent, so by going the top vent you may be able to put the stove in deeper into your hearth...key measurement is going to be the bottom to top measurement.
Good luck....maybe post all the measurements and a pic

There are lots of folks on here with hearth-mounted freestanding stoves tucked into fireplace openings. Depending on how your stove works (i.e. how much of the heat is intended to be radiant vs. convective) will dictate the placement in the opening. Most have had success with bringing the stove out as much as possible so you max the exposure. This may involve extending the hearth (which I did), which is probably worth it. You can also have custom-built surrounds that will make your stove sort of look like an insert.

There are several stoves with rear-exit or 45 degree-exit flue collars (I have the Hearthstone Phoenix, the latter of the two).

+1 on what ilikewood said. He has the same stove that I do (Lopi Answer). I have my Answer tucked all the way into my fireplace opening (it's wide enough at the back). I think the Answer can be back-vented also, which means I could have brought it out into the room more, but then I would have needed to extend my hearth, protected my mantle, etc. etc. Not what I wanted to do.

Definitely get a blower for any stove you put at least partially into alcove.

You might also consider removing some of the firebrick from the back of the masonry fireplace to widen the back-end clearance, and replacing with fireproof insulation. Check with the installers. A good one to speak with is Steve at Barry John's Chimney Service (Franklin, Massachusetts). They might even be able to remove/rebrick some of the fireplace to remove the taper and then give you your choice of inserts.