@Osito Arelano,
For me, the size was less about the amount of heat it could put out, and more about the burn time.
Having to get up in the middle of the night to load up the fire box is something of a chore. Be nice to load it at 10pm and not have to think about it till next morning. And then still have embers/coal bed to work with to get it going again vs having to restart the fire all over.
IF I had the money, I would of gone with one of these: http://www.vermontcastings.com/