So I'm about to go on mat leave with my second baby. DD is nearly 3 so will soon be at pre school most mornings. I have grand plans of getting a slow cooker and preparing all meals whilst she is out of the house and looking like domestic goddess when DH gets home from work having spent the afternoon with both kids and still manage to serve a healthy home made meal!! Are they worth it? And any tips on what size I should get, whether I need a 'medium' setting etc etc. thanks!