aga's are a status symbol amongst the inbred UK chattering class.
one of their primary advantages is they also act as an efficient room heating source.....kitchen and dinings were combined in those days, and the rest of the house was not usually heated apart from fireplaces. I don't know how smart it'd be to have one in anything other than a small house or unit in a cold temperate climate.
they were also designed to stay hot 24/7.....good for big farming families who work in the cold and are always after hot soup or food and a brew.
some cons I can think of:
- bad on low backs and arthritic knees cos you are always bending down. try putting something in and taking out of the oven. people were shorter when they were designed, and women did most of the cooking, so taller women and men are at a disadvantage.
- don't have a gas top afaik, so no good for stir frys....
- non electrics require regular servicing.
- check the energy consumption. they don't throw all that heat off for nothing.