My last (shared) house had one and I used it so much my boyfriend and I insisted on getting another for our own place. The grill is fantastic for doing quick stuff like cheese toasties without having to power on the big oven (it takes half the time to preheat). We don't use the oven much but will very occasionally use it for a ready meal when we don't want to waste the time or energy consumption of the big oven. They also do cool things like allowing you to mix microwave and oven functions, which is great for jacket potatoes as you get the crisp, oveny taste but it takes half the time.
