We have used Slow Cookers for as long as I can remember but the oval cooker is really useful, in fact I bought two, and am very pleased indeed with way they function. Being oval they will accommodate a large joint of meat the size whole large chicken. Slow cooking is particularly useful method in that you can leave a family sized one-pot meal to cook all day whilst you go out. Also, because you are cooking at lower temperature, you can take full advantage of the cheaper cuts of meat which are usually much more flavoursome.
It has to be said that a 6.5 litre Slow Cooker does cook a lot of food which is fine for a large family, or if you cook for many guests, as I often do, or if you prepare food for freezing. But just for the two of us, to offer greater flexibility, I have also purchased a 3.5 litre model that functions equally well.