All cookers have a slow cook option - the lowest oven setting.
I have had many cookers - expensive and cheap.
The best cooker I have ever had is my current one. Four years old and as good as new. It was the cheapest I could find to fit my criteria - ceramic hob, seperate grill, large fan oven and no self clean liners (the blessed things don't work!).
It is a delonghi ES602 in white - I don't know if it's still avaiable.
It is certainly much better than the expensive cookers I have bought in the past.
Having said all that, if I were buying a cooker today I would have to buy the pyrolytic self clean oven.