I had a look at a couple of cheapy cookers today. Both were only 5kg and I wasnt sure about the settings.
Is it normal for them to just have low and high?

I will be looking at some better brands and try find one with the warmer/timer setting.
Mine has warm as well but it has a timer. I think the basic ones just have high and low. I got mine from Bing Lee and it was about $80 from memory, they usually will do you a good deal.