Short answer: it depends. According to this, Is it worthwhile buying a slow cooker?, slow cooked food tastes better and looks better, though the food in a slow cooker ends up being more moist. Go with an oven if you can attend to it. Go with a slow cooker if you want to have a minimal cooking process going all day that doesn’t require you to do much more than to load up the cooker and go. An additional consideration: a slow cooker uses very little power. Go with a slow cooker if you want to minimize energy use.
Read the article and see what you think. And if you like the idea of slow cooker recipes but slow cookers aren’t for you, read it and get some ideas on how to use your oven to slow cook instead.
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