Love the fact that the negative comments are exclusively from people who dont own one, and never have!
We have a gas Aga, intentionally fitted by ourselves, and it saved us 10% on our energy bill over the year, and we were warmer in the winter. the advantage is that the kitchen is always warm, and you always have a hot oven, and as mentioend above if you are careful to leave doors open internally it can keep the whole house warm.
Negatives are that you do tend to only live in the kitchen! 😀 And you’ll burn everything you make for the first couple of weeks! Strongly recommend buying the aga cookbook to teach you how to get the best out of it, it’s not just a double over 🙂